Recording medium and audio-signal processing apparatus

ABSTRACT

A digital signal recording disc has a first area and a second area. The second area differs from the first area. The first area stores a first-channel digital audio signal and a second-channel digital audio signal. The first-channel digital audio signal results from quantizing a first-channel analog audio signal with a first quantization bit number. The second-channel digital audio signal results from quantizing a second-channel analog audio signal with a second quantization bit number. The second area stores information of the first and second quantization bit numbers.

This application is a divisional of U.S. Ser. No. 09/114,185, filed Jul.13, 1998 now U.S. Pat. No. 6,636,474.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a recording medium such as a digital videodisc, or a digital versatile disc (DVD). Also, this invention relates toan apparatus for encoding an audio signal. Furthermore, this inventionrelates to an apparatus for decoding an audio signal. In addition, thisinvention relates to an optical disc player such as a DVD (digital videodisc) player.

2. Description of the Related Art

Optical discs for storing information include digital video discs(DVD's). A standard DVD stores a combination of an audio signal and avideo signal. The audio-signal recording capacity of the standard DVD issignificantly smaller than the video-signal recording capacity thereof.It is difficult to manage time-related information of the audio signalrecorded on the standard DVD. It is difficult to read out information ofthe titles of tunes represented by the audio signal recorded on thestandard DVD.

SUMMARY OF THE INVENTION

It is a first object of this invention to provide an improved recordingmedium.

It is a second object of this invention to provide an improved apparatusfor encoding an audio signal.

It is a third object of this invention to provide an improved apparatusfor decoding an audio signal.

It is a fourth object of this invention to provide an improved opticaldisc player.

A first aspect of this invention provides a digital signal recordingdisc comprising a first area storing a first-channel digital audiosignal and a second-channel digital audio signal, the first-channeldigital audio signal resulting from quantizing a first-channel analogaudio signal with a first quantization bit number, the second-channeldigital audio signal resulting from quantizing a second-channel analogaudio signal with a second quantization bit number; and a second areadiffering from the first area and storing information of the first andsecond quantization bit numbers.

A second aspect of this invention is based on the first aspect thereof,and provides a digital signal recording disc wherein the first-channeldigital audio signal comprises a front-channel digital audio signal andthe second channel digital audio signal comprises a rear-channel digitalaudio signal, and the first and second quantization bit numbers aredifferent from each other.

A third aspect of this invention provides a digital signal recordingdisc comprising a first area storing a first-channel digital audiosignal and a second-channel digital audio signal, the first-channeldigital audio signal resulting from an analog-to-digital conversion of afirst-channel analog audio signal at a first sampling frequency, thesecond-channel digital audio signal resulting from an analog-to-digitalconversion of a second-channel analog audio signal at a second samplingfrequency; and a second area differing from the first area and storinginformation of the first and second sampling frequencies.

A fourth aspect of this invention is based on the third aspect thereof,and provides a digital signal recording disc wherein the first-channeldigital audio signal comprises a front-channel digital audio signal andthe second-channel digital audio signal comprises a rear-channel digitalaudio signal, and the first and second sampling frequencies aredifferent from each other.

A fifth aspect of this invention is based on the third aspect thereof,and provides a digital signal recording disc wherein the first-channeldigital audio signal comprises a front-channel digital audio signal andthe second-channel digital audio signal comprises a rear-channel digitalaudio signal, and the first and second sampling frequencies are equal toeach other, and wherein the rear-channel digital audio signal resultsfrom thinning (decimation), and the second area stores information ofthe thinning (the decimation).

A sixth aspect of this invention is based on the third aspect thereof,and provides a digital signal recording disc wherein the first-channeldigital audio signal comprises a front-channel digital audio signal andthe second-channel digital audio signal comprises alow-frequency-effect-channel digital audio signal, and the first andsecond sampling frequencies are equal to each other, and wherein thelow-frequency-effect-channel digital audio signal results from thinning,and the second area stores information of the thinning.

A seventh aspect of this invention provides a digital signal recordingdisc comprising a first area storing a first-channel digital audiosignal and a second-channel digital audio signal, the first-channeldigital audio signal resulting from an analog-to-digital conversion of afirst-channel analog audio signal at a first sampling frequency and afirst quantization bit number, the second-channel digital audio signalresulting from an analog-to-digital conversion of a second-channelanalog audio signal at a second sampling frequency and a secondquantization bit number, the second sampling frequency differing fromthe first sampling frequency, the second quantization bit numberdiffering from the first quantization bit number; and a second areadiffering from the first area and storing information of the first andsecond sampling frequencies and also information of the first and secondquantization bit numbers.

An eighth aspect of this invention provides a digital signal recordingdisc comprising a first area storing at least first-channel andsecond-channel digital audio signals each assigned to either a firstchannel group or a second channel group, the digital audio signal in thefirst channel group resulting from an analog-to-digital conversion of afirst analog audio signal at a first sampling frequency and a firstquantization bit number, the digital audio signal in the second channelgroup resulting from an analog-to-digital conversion of a second analogaudio signal at a second sampling frequency and a second quantizationbit number; and a second area differing from the first area and storinginformation of the first and second sampling frequencies and informationof the first and second quantization bit numbers, and also informationof the assignment of the first-channel and second-channel digital audiosignals to the first and second channel groups.

A ninth aspect of this invention is based on the seventh aspect thereof,and provides a digital signal recording disc wherein the first areastores left-channel and right-channel stereophonic digital audiosignals, the left-channel and right-channel stereophonic digital audiosignals resulting from an analog-to-digital conversion of left-channeland right-channel stereophonic analog audio signals at a third samplingfrequency, and wherein the second area stores information of the thirdsampling frequency.

A tenth aspect of this invention is based on the seventh aspect thereof,and provides a digital signal recording disc wherein the first areastores left-channel and right-channel stereophonic digital audiosignals, the left-channel and right-channel stereophonic digital audiosignals resulting from an analog-to-digital conversion of left-channeland right-channel stereophonic analog audio signals at a thirdquantization bit number, and wherein the second area stores informationof the third quantization bit number.

An eleventh aspect of this invention is based on the ninth aspectthereof, and provides a digital signal recording disc wherein theleft-channel and right-channel stereophonic digital audio signals differfrom the first-channel and second-channel digital audio signals, and thefirst area comprises a first sub area storing the first-channel and thesecond-channel digital audio signals and a second sub area storing theleft-channel and right-channel stereophonic digital audio signals.

A twelfth aspect of this invention is based on the seventh aspectthereof, and provides a digital signal recording disc wherein thefirst-channel and second-channel digital audio signals result from anencoding process selected from among an AC-3 encoding process, an MPEG-1encoding process, and an MPEG-2 encoding process.

A thirteenth aspect of this invention provides an audio-signal encodingapparatus comprising first means for quantizing a front-channel analogaudio signal into a corresponding front-channel digital audio signal ata first quantization bit number; second means for quantizing arear-channel analog audio signal into a corresponding rear-channeldigital audio signal at a second quantization bit number differing fromthe first quantization bit number; and third means for formatting thefront-channel digital audio signal, the rear-channel digital audiosignal, and information of the first and second quantization bit numbersinto a structure having first and second areas, the first areacontaining the front-channel digital audio signal and the rear-channeldigital audio signal, the second area differing from the first area andcontaining the information of the first and second quantization bitnumbers.

A fourteenth aspect of this invention provides an audio-signal encodingapparatus comprising first means for quantizing a front-channel analogaudio signal into a corresponding front-channel digital audio signal ata first sampling frequency; second means for quantizing a rear-channelanalog audio signal into a corresponding rear-channel digital audiosignal at a second sampling frequency differing from the first samplingfrequency; and third means for formatting the front-channel digitalaudio signal, the rear-channel digital audio signal, and information ofthe first and second sampling frequencies into a structure having firstand second areas, the first area containing the front-channel digitalaudio signal and the rear-channel digital audio signal, the second areadiffering from the first area and containing the information of thefirst and second sampling frequencies.

A fifteenth aspect of this invention provides an audio-signal encodingapparatus comprising first means for quantizing a front-channel analogaudio signal into a corresponding front-channel digital audio signal ata first quantization bit number and a first sampling frequency; secondmeans for quantizing a rear-channel analog audio signal into acorresponding rear-channel digital audio signal at a second quantizationbit number and a second sampling frequency, the second quantization bitnumber differing from the first quantization bit number, the secondsampling frequency differing from the first sampling frequency; andthird means for formatting the front-channel digital audio signal, therear-channel digital audio signal, information of the first and secondquantization bit numbers, and information of the first and secondsampling frequencies into a structure having first and second areas, thefirst area containing the front-channel digital audio signal and therear-channel digital audio signal, the second area differing from thefirst area and containing the information of the first and secondquantization bit numbers and the information of the first and secondsampling frequencies.

A sixteenth aspect of this invention provides an audio-signal encodingapparatus comprising first means for assigning each of first-channel andsecond-channel analog audio signals to either a first channel group or asecond channel group; second means for quantizing the analog audiosignal in the first channel group into a corresponding digital audiosignal in the first channel group at a first sampling frequency and afirst quantization bit number; third means for quantizing the analogaudio signal in the second channel group into a corresponding digitalaudio signal in the second channel group at a second sampling frequencyand a second quantization bit number; and fourth means for formattingthe digital audio signals in the first and second channel groups,information of the first and second quantization bit numbers,information of the first and second sampling frequencies, andinformation of the assignment of the first-channel and second-channelanalog audio signals to the first and second channel groups into astructure having first and second areas, the first area containing thedigital audio signals of the first and second channel groups, the secondarea differing from the first area and containing the information of thefirst and second quantization bit numbers, the information of the firstand second sampling frequencies, and the information of the assignmentof the first-channel and second-channel analog audio signals to thefirst and second channel groups.

A seventeenth aspect of this invention provides an audio-signal decodingapparatus comprising first means for extracting information of a firstquantization bit number for a front channel and information of a secondquantization bit number for a rear channel from a reproduced signal, thesecond quantization bit number differing from the first quantization bitnumber; second means for deriving a front-channel digital audio signaland a rear-channel digital audio signal from the reproduced signal;third means for decoding the front-channel digital audio signal inresponse to the information of the first quantization bit number; andfourth means for decoding the rear-channel digital audio signal inresponse to the information of the second quantization bit number.

An eighteenth aspect of this invention provides an audio-signal decodingapparatus comprising first means for extracting information of a firstsampling frequency for a front channel and information of a secondsampling frequency for a rear channel from a reproduced signal, thesecond sampling frequency differing from the first sampling frequency;second means for deriving a front-channel digital audio signal and arear-channel digital audio signal from the reproduced signal; thirdmeans for decoding the front-channel digital audio signal in response tothe information of the first sampling frequency; and fourth means fordecoding the rear-channel digital audio signal in response to theinformation of the second sampling frequency.

A nineteenth aspect of this invention provides an audio-signal decodingapparatus comprising first means for extracting information of a firstquantization bit number and a first sampling frequency for a frontchannel and information of a second quantization bit number and a secondsampling frequency for a rear channel from a reproduced signal, thesecond quantization bit number differing from the first quantization bitnumber, the second sampling frequency differing from the first samplingfrequency; second means for deriving a front-channel digital audiosignal and a rear-channel digital audio signal from the reproducedsignal; third means for decoding the front-channel digital audio signalin response to the information of the first quantization bit number andthe first sampling frequency; and fourth means for decoding therear-channel digital audio signal in response to the information of thesecond quantization bit number and the second sampling frequency.

A twentieth aspect of this invention provides an audio-signal decodingapparatus comprising first means for extracting information of a firstquantization bit number and a first sampling frequency for a firstchannel group and information of a second quantization bit number and asecond sampling frequency for a second channel group from a reproducedsignal, the second quantization bit number differing from the firstquantization bit number, the second sampling frequency differing fromthe first sampling frequency; second means for deriving a first-channeldigital audio signal and a second-channel digital audio signal from thereproduced signal, each of the derived first-channel and second-channeldigital audio signals being assigned to either the first channel groupor the second channel group; third means for extracting information ofthe assignment of the first-channel and second-channel digital audiosignals to the first and second channel groups from the reproducedsignal; and fourth means for decoding the first-channel digital audiosignal and the second-channel digital audio signal in response to theinformation of the first and second quantization bit numbers, theinformation of the first and second sampling frequencies, and theinformation of the assignment of the first-channel and second-channeldigital audio signals to the first and second channel groups.

A twenty-first aspect of this invention provides an optical disc playercomprising first means for reproducing audio packs and control packsfrom an optical disc; first and second buffers; second means foralternately writing the reproduced audio packs into the first and secondbuffers; third means for decoding the reproduced control packs intocontrol data; fourth means for decoding the audio packs in the first andsecond buffers into audio data in response to the control data; and aD/A converter for converting the audio data into an analog audio signal.

A twenty-second aspect of this invention is based on the twenty-firstaspect thereof, and provides an optical disc player wherein each of thefirst and second buffers has a capacity of 4 kilobytes.

A twenty-third aspect of this invention is based on the eighth aspectthereof, and provides a digital signal recording disc wherein the firstarea stores audio data in an audio packet, and the second area storesaudio data information ADI in the audio packet.

A twenty-fourth aspect of this invention is based on the eighth aspectthereof, and provides a digital signal recording disc wherein the firstarea comprises an audio contents block set ACBS, and the second areastores an audio-only-title audio-object attribute AOTT-AOB-ATR in audiotitle set information ATSI.

A twenty-fifth aspect of this invention is based on the sixteenth aspectthereof, and provides an audio-signal encoding apparatus furthercomprising fifth means for formatting the digital audio signals intoaudio data in audio packets; and sixth means for formatting theinformation of the first and second sampling frequencies, theinformation of the first and second quantization bit numbers, and theinformation of the assignment of the first-channel and second-channelanalog audio signals to the first and second channel groups into audiodata information ADI in the audio packets.

A twenty-sixth aspect of this invention is based on the sixteenth aspectthereof, and provides an audio-signal encoding apparatus furthercomprising fifth means for formatting the digital audio signals into anaudio contents block set ACBS; and sixth means for formatting theinformation of the first and second sampling frequencies, theinformation of the first and second quantization bit numbers, and theinformation of the assignment of the first-channel and second-channelanalog audio signals to the first and second channel groups into anaudio-only-title audio-object attribute AOTT-AOB-ATR in audio title setinformation ATSI.

A twenty-seventh aspect of this invention is based on the twentiethaspect thereof, and provides an audio-signal decoding apparatus whereinthe first means comprises means for reproducing the information of thefirst quantization bit number and the first sampling frequency, and theinformation of the second quantization bit number and the secondsampling frequency from audio data information ADI in an audio packet,and wherein the third means comprises means for reproducing theinformation of the assignment of the first-channel and second-channeldigital audio signals to the first and second channel group from theaudio data information ADI in the audio packet.

A twenty-eighth aspect of this invention is based on the twentiethaspect thereof, and provides an audio-signal decoding apparatus whereinthe first means comprises means for reproducing the information of thefirst quantization bit number and the first sampling frequency, and theinformation of the second quantization bit number and the secondsampling frequency from an audio-only-title audio-object attributeAOTT-AOB-ATR in audio title set information ATSI, and wherein the thirdmeans comprises means for reproducing the information of the assignmentof the first-channel and second-channel digital audio signals to thefirst and second channel group from the audio-only-title audio-objectattribute AOTT-AOB-ATR in audio title set information ATSI.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram of the signal recording format of a DVD-Video.

FIG. 2 is a diagram of the signal recording format of a DVD-Audioaccording to a first embodiment of this invention.

FIG. 3 is a diagram of the structure of an AMG area in FIG. 2.

FIG. 4 is a diagram of the structure of an ATS area in FIG. 2.

FIG. 5 is a diagram of the structure of an AMGI area in FIG. 3.

FIG. 6 is a diagram of the structure of an ATS-ATRT area in FIG. 5.

FIG. 7 is a diagram of the structure of an ATS-ATR area in FIG. 6.

FIG. 8 is a diagram of the structure of an ATSI area in FIG. 4.

FIG. 9 is a diagram of the structure of an ATSI-MAT area in FIG. 8.

FIG. 10 is a diagram of the structure of an ATSM-AST-ATR area in FIG. 9.

FIG. 11 is a diagram of the structure of an ATS-AST-ATRT area in FIG. 9.

FIG. 12 is a diagram of the structure of an ATS-AST-ATR area in FIG. 11.

FIG. 13 is a diagram of a sequence of packs.

FIG. 14 is a diagram of the structure of an audio pack A or a video packV.

FIG. 15 is a diagram of the structure of an audio control pack A-CONT.

FIG. 16 is a diagram of the structure of an ACD area in FIG. 15.

FIG. 17 is a diagram of the indication of an English-added Japanese tunename.

FIG. 18 is a diagram of the structure of an ASD area in FIG. 15.

FIG. 19 is a diagram of a sequence of packs.

FIG. 20 is a diagram of the relation among channels, samplingfrequencies, quantization bit numbers, data rates, and longest recordingtimes.

FIG. 21 is a diagram of the relation among channels, samplingfrequencies, quantization bit numbers, data rates, and longest recordingtimes in the case of a 2-channel plus 6-channel audio signal.

FIG. 22 is a diagram of the relation among channels, samplingfrequencies, quantization bit numbers, data rates, and longest recordingtimes in the case of a 2-channel plus 5-channel audio signal.

FIG. 23 is a diagram of the relation among channels, samplingfrequencies, quantization bit numbers, data rates, and longest recordingtimes in the case of a 6-channel audio signal.

FIG. 24 is a diagram of a DVD-Audio.

FIG. 25 is a diagram of the structure of an ACD area.

FIG. 26 is a diagram of the signal recording format of a DVD-Audioaccording to a second embodiment of this invention.

FIG. 27 is a diagram of a sequence of packs.

FIG. 28 is a diagram of the signal recording format of a DVD-Van.

FIG. 29 is a diagram of the signal recording format of a DVD-Video.

FIG. 30 is a diagram of the signal recording format of a DVD-Avd.

FIG. 31 is a diagram of the structure of an AOTT-AOB-ATR area.

FIG. 32 is a diagram of channel assignment.

FIG. 33 is a diagram of the structure of a linear PCM audio pack.

FIG. 34 is a diagram of the structure of an ADI area in FIG. 33.

FIG. 35 is a diagram of the structure of an AOTT-VOB-AST-ATR area.

FIG. 36 is a block diagram of an audio-signal encoding apparatusaccording to a third embodiment of this invention.

FIG. 37 is a block diagram of a signal processing circuit in FIG. 36.

FIG. 38 is a block diagram of a DVD-Audio player including anaudio-signal decoding apparatus according to a fourth embodiment of thisinvention.

FIG. 39 is a block diagram of a DVD-Audio player including anaudio-signal decoding apparatus according to a fifth embodiment of thisinvention.

FIG. 40 is a block diagram of a DVD-Audio player including anaudio-signal decoding apparatus according to a sixth embodiment of thisinvention.

FIG. 41 is a block diagram of a DVD-Audio player including anaudio-signal decoding apparatus according to a seventh embodiment ofthis invention.

FIG. 42 is a block diagram of an optical disc player according to aneighth embodiment of this invention.

FIG. 43 is a block diagram of an optical disc player according to aninth embodiment of this invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment

FIG. 1 shows the signal recording format of a DVD-Video (digital videodisc-video). As shown in FIG. 1, the DVD-Video has a first area assignedto a video manager VMG. The VMG area is followed by a sequence of secondand later areas assigned to video title sets VTS respectively.

Each VTS area has a sequence of an area assigned to VTS informationVTSI, one or more areas assigned to respective video contents block setsVCBS, and an area assigned to VTS information VTSI. The first videocontents block set VCBS stores menu information for indicating a menupicture.

Each VCBS area has a sequence of areas assigned to video contents blocksVCB respectively. Each video contents block VCB corresponds to one videotitle.

Each VCB area has a sequence of areas corresponding to chaptersrespectively. Each chapter contains information representing a part of atitle which is denoted by PTT.

Each chapter has a sequence of cells. Each cell has a sequence of VCBunits VCBU. Each VCB unit VCBU has a sequence of packs. Each pack has2,048 bytes.

In each VCB unit VCBU, a first pack is a control pack CONT followed by asequence of packs including video packs V, audio packs A, and subpicture packs SP. The control pack CONT is assigned to information forcontrolling video packs V following the control pack CONT. The controlinformation includes video-pack-synchronizing information. Each audiopack is assigned to audio data.

FIG. 2 shows the signal recording format of a DVD-Audio (digital videodisc-audio) according to a first embodiment of this invention. TheDVD-Audio is compatible with a DVD-Video (see FIG. 1). As shown in FIG.2, the DVD-Audio has a first area assigned to an audio manager AMG. TheAMG area is followed by a sequence of second and later areas assigned toaudio title sets ATS respectively.

Each ATS area has a sequence of an area assigned to ATS informationATSI, one or more areas assigned to respective audio contents block setsACBS, and an area assigned to ATS information ATSI. The ATS informationATSI indicates play time lengths of respective tunes represented byaudio data in the audio contents block sets ACBS. The play time lengthsof the respective tunes are expressed in terms of real time. The firstaudio contents block set ACBS stores menu information for indicating amenu picture.

Each ACBS area has a sequence of areas assigned to audio contents blocksACB respectively. Each audio contents block ACB corresponds to one audiotitle.

Each ACB area has a sequence of areas corresponding to tracksrespectively. Each track contains information representing a part of atitle which is denoted by PTT.

Each track has a sequence of indexes (cells). Each index has a sequenceof ACB units ACBU. Each ACB unit ACBU has a sequence of packs. Each packhas 2,048 bytes.

In each ACB unit ACBU, a first pack is an audio control pack A-CONTfollowed by a sequence of packs including audio packs A1 and A2 andvideo packs V. The audio control pack A-CONT is assigned to informationfor managing an audio signal (audio data) in audio packs A1 and A2following the audio control pack A-CONT. The managing information in theaudio control pack A-CONT is basically similar to TOC (table ofcontents) information in a compact disc (CD). The managing informationcontains audio-pack-synchronizing information. Each audio pack A1 or A2is assigned to audio data. The video packs V are assigned to video dataand non-audio data such as closed caption (CC) data. The video packs Vmay be omitted from the ACB unit ACBU.

It should be noted that each ACB unit ACBU may further include a controlpack CONT.

As shown in FIG. 3, the AMG area (see FIG. 2) stores audio managerinformation AMGI, an audio contents block set AMGM-ACBS for an AMG menu,and backup audio manager information AMGI. The audio manager informationAMGI has TOC (table of contents) information. The audio contents blockset AMGM-ACBS has presentation control information PCI and data searchinformation DSI which are control information pieces respectively.

As shown in FIG. 4, the ATS area (see FIG. 2) stores audio title setinformation ATSI, an audio contents block set ATSM-ACBS for an ATS menu,an audio contents block set ATSA-ACBS for an ATS title, and backup audiotitle set information ATSI. The audio title set information ATSI has TOC(table of contents) information. Each of the audio contents block setsATSM-ACBS and ATSA-ACBS has presentation control information PCI anddata search information DSI.

As shown in FIG. 5, the audio manager information AMGI (see FIG. 3) hasa management table AMGI-MAT therefor, a title search pointer tableT-SRPT, an audio manager menu program chain information unit tableAMGM-PGCI-UT, a parental management information table PTL-MAIT, an audiotitle set attribute table ATS-ATRT, a text data manager TXTDT-MG, anaudio manager menu cell (index) address table AMGM-C-ADT, and an audiomanager menu audio contents block unit address map AMGM-ACBU-ADMAP.

As shown in FIG. 6, the audio title set attribute table ATS-ATRT (seeFIG. 5) has audio title set attribute table information ATS-ATRTI, audiotitle set attribute search pointers ATS-ATR-SRP#1, ATS-ATR-SRP#2, . . ., ATS-ATR-SRP#n for respective “n” audio title sets ATS, and audio titleset attribute data pieces ATS-ATR-#1, ATS-ATR-#2, . . . , ATS-ATR-#n forthe respective “n” audio title sets ATS.

As shown in FIG. 7, each of the audio title set attribute data piecesATS-ATR-#1, ATS-ATR-#2, . . . , ATS-ATR-#n (see FIG. 6) represents anend address ATS-ATR-EA of the audio title set attribute, a categoryATS-CAT of the audio title set, and audio title set attributeinformation ATS-ATRI.

As shown in FIG. 8, the audio title set information ATSI (see FIG. 4)has a management table ATSI-MAT for the audio title set informationATSI, a part-of-title search pointer table ATS-PTT-SRPT for the audiotitle set, a program chain information table ATS-PGCIT for the audiotitle set, a PGCI unit table ATSM-PGCI-UT for the audio title set menu,a time map table ATS-TMAPT for the audio title set, a cell (index)address table ATSM-C-ADT for the audio title set menu, an audio contentsblock unit address map ATSM-ACBU-ADMAP for the audio title set menu, acell (index) address table ATS-C-ADT for the audio title set, and anaudio contents block unit address map ATS-ACBU-ADMAP for the audio titleset.

As shown in FIG. 9, the audio title set information management tableATSI-MAT (see FIG. 8) has an identifier ATS-ID for the audio title set,an end address ATS-EA of the audio title set, an end address ATSI-EA forthe audio title set information, a version number VERN of thespecifications of the DVD-Audio, a category ATS-CAT of the audio titleset, an end address ATSI-MAT-EA of the audio title set informationmanagement table, a start address ATSM-ACBS-SA of the ATS menu audiocontents block set, a start address ATSA-ACBS-SA of the ATS title audiocontents block set, a start address ATS-PTT-SRPT-SA of the audio titleset part-of-title search pointer table, a start address ATS-PGCIT-SA ofthe audio title set program chain information table, a start addressATSM-PGCI-UT-SA of the audio title set menu program chain informationunit table, a start address ATS-TMAPT-SA of the audio title set time maptable, a start address ATSM-C-ADT-SA of the audio title set menu celladdress table, a start address ATSM-ACBU-ADMAP-SA of the ATS menu audiocontents block unit address map, an ATS menu audio stream attributeATSM-AST-ATR, the number ATS-AST-Ns of audio streams in the audio titleset, and an ATS audio stream attribute table ATS-AST-ATRT.

As shown in FIG. 10, the ATS menu audio stream attribute ATSM-AST-ATR(see FIG. 9) has a sequence of 8 bytes, that is, 64 bits b63, b62, b61,. . . , b1, b0. A set of the bits b63, b62, and b61 represents an audioencoding mode selected from among a Dolby AC-3 encoding mode, anencoding mode corresponding to MPEG-1 or MPEG-2 without any extensionbit stream, an encoding mode corresponding to MPEG-2 with an extensionbit stream, a first linear PCM audio encoding mode, and a second linearPCM audio encoding mode. The second linear PCM audio encoding mode is ofa type containing a sub type corresponding to 2 channels plus 5channels, a sub type corresponding to 2 channels plus 6 channels, and asub type corresponding to 2 channels plus 8 channels. Specifically, abit sequence of “000” is assigned to the Dolby AC-3 encoding mode. A bitsequence of “010” is assigned to the encoding mode corresponding toMPEG-1 or MPEG-2 without any extension bit stream. A bit sequence of“011” is assigned to the encoding mode corresponding to MPEG-2 with anextension bit stream. A bit sequence of “100” is assigned to the firstlinear PCM audio encoding mode. A bit sequence of “101” is assigned tothe second linear PCM audio encoding mode.

A set of the bits b55 and b54 in the ATS menu audio stream attributeATSM-AST-ATR represents information of quantization/dynamic rangecontrol (DRC). When the audio encoding mode is “000”, the information ofquantization/DRC is set to “11”. When the audio encoding mode is “010”or “011”, a bit sequence of “00” which relates to the information ofquantization/DRC represents the absence of dynamic control data from theMPEG audio stream. When the audio encoding mode is “010” or “01 1”, abit sequence of “01” which relates to the information ofquantization/DRC represents the presence of dynamic control data in theMPEG audio stream. When the audio encoding mode is “010” or “101”, a bitsequence of “00” which relates to the information of quantization/DRCrepresents that each of channels (two stereophonic channels) has 16 bitsfor every signal sample. When the audio encoding mode is “100” or “101”,a bit sequence of “01” which relates to the information ofquantization/DRC represents that each of channels (two stereophonicchannels) has 20 bits for every signal sample. When the audio encodingmode is “100” or “101”, a bit sequence of “10” which relates to theinformation of quantization/DRC represents that each of channels (twostereophonic channels) has 24 bits for every signal sample.

A set of the bits b53 and b52 in the ATS menu audio stream attributeATSM-AST-ATR represents a sampling frequency “fs” related to each of twostereophonic channels. Specifically, a bit sequence of “00” indicatesthat the sampling frequency “fs” is equal to 48 kHz. A bit sequence of“01” indicates that the sampling frequency “fs” is equal to 96 kHz. Abit sequence of “10” indicates that the sampling frequency “fs” is equalto 192 kHz.

A set of the bits b50, b49, and b48 in the ATS menu audio streamattribute ATSM-AST-ATR represents the number of audio channels.Specifically, a bit sequence of “000” indicates that there is only onechannel (“monaural”). A bit sequence of “001” indicates that there aretwo stereophonic channels. A bit sequence of “010” indicates that thereare three channels. A bit sequence of “011” indicates that there arefour channels. A bit sequence of “100” indicates that there are twostereophonic channels plus five channels. A bit sequence of “101”indicates that there are two stereophonic channels plus six channels. Abit sequence of “110” indicates that there are seven channels. A bitsequence of “111” indicates that there are two stereophonic channelsplus eight channels.

As shown in FIG. 11, the ATS audio stream attribute table ATS-AST-ATRT(see FIG. 9) has attributes ATS-AST-ATR of respective ATS audio streamsATS-AST#0, ATS-AST#1, . . . , ATS-AST#7. Each of the ATS audio streamattributes ATS-AST-ATR has 8 bytes. Accordingly, the total number ofbytes representing the ATS audio stream attribute table ATS-AST-ATRT isequal to 64.

As shown in FIG. 12, each ATS audio stream attribute ATS-AST-ATR (seeFIG. 11) has a sequence of 8 bytes, that is, 64 bits b63, b62, b61, . .. , b1, b0. A set of the bits b63, b62, and b61 in the ATS audio streamattribute ATS-AST-ATR represents an audio encoding mode as in the ATSmenu audio stream attribute ATSM-AST-ATR (see FIG. 10). A set of thebits b55 and b54 in the ATS audio stream attribute ATS-AST-ATRrepresents information of quantization/dynamic range control (DRC) as inthe ATS menu audio stream attribute ATSM-AST-ATR (see FIG. 10). A set ofthe bits b53 and b52 in the ATS audio stream attribute ATS-AST-ATRrepresents a sampling frequency “fs” as in the ATS menu audio streamattribute ATSM-AST-ATR (see FIG. 10). A set of the bits b50, b49, andb48 in the ATS audio stream attribute ATS-AST-ATR represents the numberof audio channels as in the ATS menu audio stream attribute ATSM-AST-ATR(see FIG. 10).

The bit b60 in the ATS audio stream attribute ATS-AST-ATR representsinformation of multichannel extension ME. A set of the bits b59 and b58in the ATS audio stream attribute ATS-AST-ATR represents an audio type.

A set of the bits b57 and b56 in the ATS audio stream attributeATS-AST-ATR represents an audio application mode. Specifically, a bitsequence of “01” indicates a karaoke mode. A bit sequence of “10”indicates a surround mode. A bit sequence of “11” indicates a 2-channelplus surround mode.

A set of the bits b47 and b46 in the ATS audio stream attributeATS-AST-ATR represents information of thinning (decimating) the relatedaudio stream AST. Specifically, a bit sequence of “00” indicates thatthinning corresponds to “full” ( 1/1, absence of thinning). A bitsequence of “01” indicates that thinning corresponds to “half” (½). Abit sequence of “10” indicates that thinning corresponds to “quarter”(¼).

A set of the bits b45 and b44 in the ATS audio stream attributeATS-AST-ATR represents information of thinning data in the related lowfrequency effect (LFE) channel. Specifically, a bit sequence of “00”indicates that thinning corresponds to “full” ( 1/1, absence ofthinning). A bit sequence of “01” indicates that thinning corresponds to“half” (½). A bit sequence of “10” indicates that thinning correspondsto “quarter” (¼).

For the audio stream AST#0, the bits b50, b49, and b48 in the ATS menuaudio stream attribute ATSM-AST-ATR (see FIG. 10) are fixed to “001”indicating that there are two stereophonic channels. For the audiostream AST#1, the bits b50, b49, and b48 in the ATS menu audio streamattribute ATSM-AST-ATR (see FIG. 10) are fixed to “010” indicating thatthere are three channels.

In the case where a recorded audio signal of one title has twostereophonic channels plus six channels, 2-channel stereophonic signalsare assigned to the audio stream AST#0 and 3-channel front signals among6-channel signals are assigned to the audio stream AST#1, and 2-channelrear signals and a 1-channel LFE signal are assigned to the audio streamAST#2. In this case, a signal of “3” indicating use of three audiostreams (the audio stream AST#0, AST#1, and AST#2) is placed in themanagement table AMGI-MAT within the audio manager information AMGI ofFIG. 5 and also the management table ATSI-MAT within the audio title setinformation ATSI of FIG. 8.

An explanation will be given of the case where an original analog audiosignal has two stereophonic channels plus six channels, and the originalanalog audio signal is processed into a digital audio signal underconditions indicated below before the digital audio signal is recorded.The 2-channel analog stereophonic signals are sampled at a frequency“fs” of 48 kHz, and are quantized with a quantization bit number of 20.The 3-channel analog front signals are sampled at a frequency “fs” of 96kHz, and are quantized with a quantization bit number of 16. The2-channel analog rear signals and the 1-channel analog LFE signal aresampled at a frequency “fs” of 48 kHz, and are quantized with aquantization bit number of 16. The resultant 8-channel digital signalsare unthinned. In this case, information pieces of attributes ofstereophonic two channels are set in the ATS menu audio stream attributeATSM-AST-ATR of FIG. 10 as follows. The bits b63, b62, and b61 in theATS menu audio stream attribute ATSM-AST-ATR are set to “101”representing the second linear PCM audio encoding mode which is of thetype containing the sub type corresponding to 2 channels plus 5channels, the sub type corresponding to 2 channels plus 6 channels, andthe sub type corresponding to 2 channels plus 8 channels. The bits b55and b54 in the ATS menu audio stream attribute ATSM-AST-ATR are set to“01” representing that each of two stereophonic channels has 20 bits forevery signal sample. The bits b53 and b52 in the ATS menu audio streamattribute ATSM-AST-ATR are set to “00” indicating that the samplingfrequency “fs” is equal to 48 kHz.

The bits b50, b49, and b48 in the ATS menu audio stream attributeATSM-AST-ATR are set to “101” indicating that there are two stereophonicchannels plus six channels.

In the above-mentioned case, information pieces of attributes are set inthe ATS audio stream attribute ATS-AST-ATR of FIG. 12 for the audiostream AST#0 as follows. The bits b63, b62, and b61 in the ATS audiostream attribute ATS-AST-ATR are set to “101” representing the secondlinear PCM audio encoding mode which is of the type containing the subtype corresponding to 2 channels plus 5 channels, the sub typecorresponding to 2 channels plus 6 channels, and the sub typecorresponding to 2 channels plus 8 channels. The bits b55 and b54 in theATS audio stream attribute ATS-AST-ATR are set to “01” representing thateach of two stereophonic channels has 20 bits for every signal sample.The bits b53 and b52 in the ATS audio stream attribute ATS-AST-ATR areset to “00” indicating that the sampling frequency “fs” is equal to 48kHz. The bits b50, b49, and b48 in the ATS audio stream attributeATS-AST-ATR are set to “001” indicating that there are two stereophonicchannels. The bits b57 and b56 in the ATS audio stream attributeATS-AST-ATR are set to “11” indicating the 2-channel plus surround mode.As information of thinning the related audio stream AST#0, the bits b47and b46 in the ATS audio stream attribute ATS-AST-ATR are set to “00”indicating that thinning corresponds to “full” ( 1/1, absence ofthinning). As information of thinning data in the related LFE channel,the bits b45 and b44 in the ATS audio stream attribute ATS-AST-ATR areset to “00” indicating that thinning corresponds to “full” ( 1/1,absence of thinning).

In the above-mentioned case, information pieces of attributes are set inthe ATS audio stream attribute ATS-AST-ATR of FIG. 12 for the audiostream AST#1 as follows. The bits b63, b62, and b61 in the ATS audiostream attribute ATS-AST-ATR are set to “101” representing the secondlinear PCM audio encoding mode which is of the type containing the subtype corresponding to 2 channels plus 5 channels, the sub typecorresponding to 2 channels plus 6 channels, and the sub typecorresponding to 2 channels plus 8 channels. The bits b55 and b54 in theATS audio stream attribute ATS-AST-ATR are set to “00” representing thateach channel has 16 bits for every signal sample. The bits b53 and b52in the ATS audio stream attribute ATS-AST-ATR are set to “01” indicatingthat the sampling frequency “fs” is equal to 96 kHz. The bits b50, b49,and b48 in the ATS audio stream attribute ATS-AST-ATR are set to “010”indicating that there are three channels. The bits b57 and b56 in theATS audio stream attribute ATS-AST-ATR are set to “11” indicating the2-channel plus surround mode. As information of thinning the relatedaudio stream AST# 1, the bits b47 and b46 in the ATS audio streamattribute ATS-AST-ATR are set to “00” indicating that thinningcorresponds to “full” ( 1/1, absence of thinning). As information ofthinning data in the related LFE channel, the bits b45 and b44 in theATS audio stream attribute ATS-AST-ATR are set to “00” indicating thatthinning corresponds to “full” ( 1/1, absence of thinning).

In the above-mentioned case, information pieces of attributes are set inthe ATS audio stream attribute ATS-AST-ATR of FIG. 12 for the audiostream AST#2 as follows. The bits b63, b62, and b61 in the ATS audiostream attribute ATS-AST-ATR are set to “101” representing the secondlinear PCM audio encoding mode which is of the type containing the subtype corresponding to 2 channels plus 5 channels, the sub typecorresponding to 2 channels plus 6 channels, and the sub typecorresponding to 2 channels plus 8 channels. The bits b55 and b54 in theATS audio stream attribute ATS-AST-ATR are set to “00” representing thateach channel has 16 bits for every signal sample. The bits b53 and b52in the ATS audio stream attribute ATS-AST-ATR are set to “00” indicatingthat the sampling frequency “fs” is equal to 48 kHz. The bits b50, b49,and b48 in the ATS audio stream attribute ATS-AST-ATR are set to “010”indicating that there are three channels. The bits b57 and b56 in theATS audio stream attribute ATS-AST-ATR are set to “1” indicating the2-channel plus surround mode. As information of thinning the relatedaudio stream AST#2, the bits b47 and b46 in the ATS audio streamattribute ATS-AST-ATR are set to “00” indicating that thinningcorresponds to “full” ( 1/1, absence of thinning). As information ofthinning data in the related LFE channel, the bits b45 and b44 in theATS audio stream attribute ATS-AST-ATR are set to “00” indicating thatthinning corresponds to “full” ( 1/1, absence of thinning).

With reference to FIG. 13, there is a sequence of packs containingcontrol packs CONT, audio packs A, audio control packs A-CONT, and videopacks V. Audio streams are recorded in the audio packs A. Each VCB unitVCBU has a set of successive packs which corresponds to a time length of0.4 second to 1.0 second. The total number of packs in one VCB unit VCBUis arbitrary. The first pack in each VCB unit VCBU is a control packCONT. On the other hand, each ACB unit ACBU has a set of successivepacks which corresponds to a time length of 0.5 second to 1.0 second.The total number of packs in one ACB unit ACBU is arbitrary. The firstpack in each ACB unit ACBU is an audio control pack A-CONT. An audiocontrol pack A-CONT in each ACB unit ACBU in a DVD-Audio is located at aplace corresponding to a third pack in a VCB unit VCBU in a DVD-Video.

Basically, audio control packs A-CONT are spaced at intervalscorresponding to 0.5 second. In the boundary between indexes (cells),audio control packs A-CONT are spaced at intervals corresponding to atime of 0.5 second to 1.0 second.

Time (GOF, group of audio frames) related to audio is represented byeach audio control pack A-CONT, and a related data position is decidedby an audio frame number, a first access unit pointer, and the number offrame headers. Audio packs A immediately before audio control packsA-CONT may be padded to provide 0.5-second intervals between the audiocontrol packs A-CONT.

Audio signal segments stored in respective neighboring audio packs Ahave a predetermined relation with each other. In the case where arecorded audio signal is of the stereophonic type, neighboring audiopacks A store a left-channel signal segment and a right-channel signalsegment, respectively. In the case where a recorded audio signal is ofthe multiple-channel type (the 5-channel type, the 6-channel type, orthe 8-channel type), neighboring audio packs A store different channelsignal segments, respectively.

Each video pack V stores information of a picture which relates to audiosignal segments in audio packs A near the video pack V.

As shown in FIG. 14, each of audio packs A and video packs V has asequence of 4-byte pack start information, 6-byte SCR (system clockreference) information, 3-byte mux rate information, 1-byte stuffinginformation, and 2,034-byte packet-form user data. Thus, each of audiopacks A and video packs V has 2,048 bytes. In each audio pack A or videopack V, pack start information, SCR information, mux rate information,and stuffing information compose a 14-byte pack header. SCR informationin each audio pack A or video pack V serves as a time stamp.

A time stamp in a first audio pack A among audio packs related to onetitle is set to “1”. Time stamps in second and later audio packs relatedto the same title are set to serial numbers “2”, “3”, “4”, . . . ,respectively. The serially-numbered time stamps enable management oftimes of audio packs A related to the same title.

As shown in FIG. 15, each audio control pack A-CONT has a sequence of a14-byte pack header, a 24-byte system header, a 1003-byte audiocharacter display (ACD) packet, and a 1007-byte audio search data (ASD)packet. The ACD packet has a sequence of a 6-byte packet header, a1-byte area assigned to sub stream identification (ID) information, a636-byte area assigned to audio character display (ACD) information, anda 360-byte reserved area. The ASD packet has a sequence of a 6-bytepacket header, a 1-byte area assigned to sub stream identification (ID)information, and a 1000-byte area assigned to audio search data (ASD).

As shown in FIG. 16, the 636-byte ACD information area has a 48-bytearea assigned to general information, a 294-byte area for a firstlanguage, and a 294-byte area for a second language. The 294-byte areafor the first language is divided into a 93-byte name space area, afirst 93-byte free space area, a second 93-byte free space area, and a15-byte data pointer area. Similarly, the 294-byte area for the secondlanguage is divided into a 93-byte name space area, a first 93-byte freespace area, a second 93-byte free space area, and a 15-byte data pointerarea. In the case where the first language is Japanese, the 93-byte namespace area for the first language stores data representing anEnglish-added Japanese tune name as shown in FIG. 17. In the case wherethe second language is English, the 93-byte name space area for thesecond language stores data representing an English tune name. The firstand second languages may be decided by the publisher of the presentDVD-Audio.

The 48-byte general information area in the ACD information area of FIG.16 has a 16-byte area assigned to service level information, a 12-bytearea assigned to language code information, a 6-byte area assigned tocharacter set code information, a 6-byte area assigned to display iteminformation, a 2-byte area assigned to information of the differencefrom the previous ACD information, and a 6-byte reserved area. The16-byte service level information represents a display size, a displaytype, a discrimination among audio, video, and sub picture SP, and astream. Characters designated by the 48-byte general information aremandatory while bit maps designated thereby are optional. The 12-bytelanguage code information has a first 2-byte information piecedesignating the first language, and a second 2-byte information piecedesignating the second language. Eight or less languages can bedesignated in one file. Regarding the first and second languages, theEnglish language is mandatory.

The 6-byte character set code information represents 15 or lesscharacter code words corresponding to language code words. The 6-bytecharacter set code information has a 1-byte information piecerepresenting whether the first and second languages are present orabsent, and also representing the types of the first and secondlanguages. For example, a first language code word corresponds to the“ISO646” standards and a second language code word corresponds to the“ISO8859-1” standards while a third language code word corresponds tothe “MS-JIS” standards.

The 6-byte display item information represents whether the free spaces(see FIG. 16) for the first and second languages and the data pointers(see FIG. 16) for the first and second languages are present or absent.The 6-byte display item information contains related ID (identification)information. It should be noted that the name spaces (see FIG. 16) forthe first and second languages are mandatory. An information piece of atitle name, an information piece of a music name, and an informationpiece of an artist name are stored in the name space areas for the firstand second languages.

As shown in FIG. 18, the 1000-byte audio search data (ASD) area (seeFIG. 15) is divided into a 16-byte area assigned to general information,an 8-byte area assigned to information of the present number, a 16-bytearea assigned to information of the present time, an 8-byte areaassigned to title set search information, an 8-byte area assigned totitle search information, a 404-byte area assigned to track searchinformation, a 408-byte area assigned to index search information, an80-byte area assigned to highlight search information, and a 52-bytereserved area.

The 8-byte present number information area in FIG. 18 is divided into a2-byte area assigned to BCD information of the present title number ofthe related title set, a 2-byte area assigned to BCD information of thepresent track number of the related title set, a 2-byte area assigned toBCD information of the present index number of the related track, and a2-byte reserved area.

The 16-byte present time information area in FIG. 18 is divided into a4-byte area assigned to BCD information of a playback time of therelated track, a 4-byte area assigned to BCD information of a remainingplayback time of the related track, a 4-byte area assigned to BCDinformation of an absolute time of the related title, and a 4-byte areaassigned to BCD information of a remaining absolute time of the relatedtitle.

The 8-byte title set search information area in FIG. 18 is divided intoa 4-byte area assigned to information of an order number of a firstsector regarding the related title set, and a 4-byte area assigned toinformation of an order number of a final sector regarding the relatedtitle set.

The 8-byte title search information area in FIG. 18 is divided into a4-byte area assigned to information of an order number of a first sectorin the related title, and a 4-byte area assigned to information of anorder number of a final sector in the related title.

The 404-byte track search information area in FIG. 18 is divided into a4-by-99-byte area assigned to information of order numbers of sectorsand order numbers of tracks in the related title, a 4-byte area assignedto information of an order number of a first track in the related title,and a 4-byte area assigned to information of an order number of a finaltrack in the related title.

The 408-byte index search information area in FIG. 18 is divided into a4-by-100-byte area assigned to information of order numbers of sectorsand order numbers of indexes in the related track, a 4-byte areaassigned to information of an order number of a first index in therelated track, and a 4-byte area assigned to information of an ordernumber of a final index in the related track.

The 80-byte highlight search information area in FIG. 18 is divided intoa 4-by-10-byte area assigned to information of order numbers ofin-sectors in the related track, and a 4-by-10-byte area assigned toinformation of order numbers of out-sectors in the related track.

With reference back to FIGS. 2 and 13, in the DVD-Audio, an audiocontrol pack A-CONT precedes a plurality of audio packs A. The audiocontrol pack A-CONT stores information for managing audio signalsegments stored in the following audio packs A. In the DVD-Audio, audiodata can be independent of video data. The DVD-Audio has a greater audiorecording capacity than that of the DVD-Video. Audio control packsA-CONT in the DVD-Audio enable management of audio-related time.Character information representing, for example, a tune name, can beread out from an audio control pack A-CONT.

In the DVD-Audio, each audio control pack A-CONT stores managinginformation (TOC information) representing a title, a start address, anda play time. During playback of the audio signal from the DVD-Audio,information requested by the user can be read out from audio controlpacks A-CONT and be indicated on a display of a DVD-Audio player. Theuser can decide a desired position of restart of playback by referringto the indicated information. Playback can be restarted from the desiredposition in response to user's request.

In the DVD-Audio, audio manager information AMGI and audio title setinformation ATSI have TOC information. Before playback of the audiosignal from the DVD-Audio, the TOC information can be read out from theDVD-Audio and be stored into a memory within a DVD-Audio player.Information requested by the user can be read out from the memory and beindicated on a display of the DVD-Audio player. The user can decide adesired position of start of playback by referring to the indicatedinformation. Playback can be started from the desired position inresponse to user's request.

Regarding the DVD-Audio, it is possible to implement a search for and arandom access to a title, a tune, and an index. In addition, it ispossible to implement a random access, a time search, and a tune-headsearch in unit of GOF (group of audio frames). Furthermore, it ispossible to manage title-related time, tune-related time, andindex-related time on a real-time basis.

Video packs V in the DVD-Audio make it possible to manage and indicatethe present time and the remaining play time of a tune or a title.

It should be noted that the pack sequence of FIG. 13 may be replaced bya pack sequence of FIG. 19 from which video packs V and control packsCONT are omitted.

As shown in FIG. 20, the time length of an audio signal which can berecorded on a DVD-Audio depends on the number of channels of the audiosignal, a sampling frequency “fs”, and a quantization bit number. Thetime length ranges from several tens of minutes to about four hundredminutes.

FIG. 21 shows the relation among the time length of a 2-channel plus6-channel audio signal which can be recorded on a DVD-Audio, a samplingfrequency “fs”, and a quantization bit number. In this case, the 6channels are 3 front channels, 2 rear channels, and one LFE channel. InFIG. 21, the time length ranges from 62 minutes to 70 minutes.

FIG. 22 shows the relation among the time length of a 2-channel plus5-channel audio signal which can be recorded on a DVD-Audio, a samplingfrequency “fs”, and a quantization bit number. In this case, the 5channels are 3 front channels and 2 rear channels. In FIG. 22, the timelength ranges from 62 minutes to 67 minutes.

FIG. 23 shows the relation among the time length of a 6-channel audiosignal which can be recorded on a DVD-Audio, a sampling frequency “fs”,and a quantization bit number. In this case, the 6 channels are 3 frontchannels, 2 rear channels, and one LFE channel. In FIG. 23, the timelength ranges from 65 minutes to 86 minutes.

With reference to FIG. 24, a DVD-Audio D has an inner area D1 and anouter area D2. The outer area D2 extends outward of the inner area D1.The DVD-Audio D is applied to a 2-channel plus multiple-channel audiosignal. Audio streams related to the multiple-channels are stored in theinner area D1 while audio streams related to the 2-channels are storedin the outer area D2.

As previously explained, the audio encoding mode can be selected fromamong the Dolby AC-3 encoding mode, the encoding mode corresponding toMPEG-1 or MPEG-2 without any extension bit stream, the encoding modecorresponding to MPEG-2 with an extension bit stream, the first linearPCM audio encoding mode, and the second linear PCM audio encoding mode.In the case where the audio encoding mode agrees with the Dolby AC-3encoding mode or the MPEG-1 or MPEG-2 encoding mode, it is preferablethat a sampling frequency “fs” and a quantization bit number forchannels except front channels are equal to standard values while asampling frequency “fs” and a quantization bit number for the frontchannels are different from the standard values.

It should be noted that the 636-byte ACD information area in FIG. 16 maybe replaced by a 636-byte ACD information area in FIG. 25. The 636-byteACD information area in FIG. 25 has a 48-byte area assigned to generalinformation, a 294-byte area for one language, and a 294-byte areaassigned to audio reproduction control information. The 294-byte areafor the language stores information used to indicate a tune name asaudio navigation. The 294-byte area for the language is divided into a93-byte name space area, a first 93-byte free space area, a second93-byte free space area, and a 15-byte data pointer area.

The 294-byte audio reproduction control information area is divided intoa 250-byte area assigned to the audio reproduction control information,and a 44-byte reserved area. The 250-byte audio reproduction controlinformation area is divided into ten 25-byte areas assigned to differentaudio reproduction control information pieces respectively. Each of the25-byte audio reproduction control information areas is divided into a20-byte area assigned to information of a graphic equalizer, a 3-bytearea assigned to information of level balance, and a 2-byte areaassigned to information of addition of echo sound. During playback of anaudio signal from a DVD-Audio, one of the audio reproduction controlinformation pieces can be selected by a user to control the quality ofreproduced sounds. The audio reproduction control information pieces aredata recommended by a professional mixer which can optimize the qualityof reproduced sounds in accordance with a type of a tune and alsoplaying and recording conditions of the tune. The 44-byte reserved areacan store information of mixing coefficients for mixing down a 6-channelaudio signal into a 2-channel audio signal.

Second Embodiment

FIG. 26 shows the signal recording format of a DVD-Audio (digital videodisc-audio) according to a second embodiment of this invention. TheDVD-Audio in FIG. 26 has an area assigned to an audio title setdirectory ATS_D including a number of audio title sets ATS. TheDVD-Audio in FIG. 26 does not have any area assigned to a video titleset VTS.

The ATS_D area has an area assigned to an audio manager AMG, an areaassigned to an audio manager menu AMGM, an area assigned to a firstaudio title set ATS<1>, and an area assigned to a second audio title setATS<2>. The audio manager AMG contains audio manager information AMGIfor managing the audio title sets ATS<1> and ATS<2>. The audio managerAMG has a structure similar to that in FIG. 3.

The audio title sets ATS<1> and ATS<2> are similar in structure. Thus,only the audio title set ATS<1> will be explained hereinafter.

As shown in FIG. 27, the audio title set ATS<1> has a sequence of packsincluding audio packs A, still-picture packs SPCT, and real-timeinformation packs RTI. The pack sequence in the audio title set ATS<1>does not have any audio control pack A-CONT. There is about onestill-picture pack SPCT per track. The still-picture packs SPCT arevideo packs V of a given type. Each of the still-picture packs SPCT hasa sequence of a pack header, a packet header, and data representative ofa still picture. The real-time information packs RTI correspond to ACDpackets in audio control packs A-CONT, respectively. Each of thereal-time information packs RTI has a sequence of a pack header, apacket header, sub stream identification information, ISRC information,private header length information, identification information forreal-time information, stuffing bytes, and data representative of realtime (audio character display data).

FIG. 28 shows the signal recording format of a DVD-Van (digital videodisc-video plus audio navigation). The DVD-Van in FIG. 28 has an areaassigned to a video title set directory VTS_D including a number ofvideo title sets VTS, and an area assigned to an audio navigation titleset directory ANV-TS_D. The video title set VTS corresponds to DVD videodata while the audio navigation title set ANV-TS corresponds to audionavigation data. The video title set VTS has a structure similar to thatin FIG. 1.

The VTS_D area in FIG. 28 has an area assigned to a video manager VMG,an area assigned to a video manager menu VMGM, an area assigned to afirst video title set VTS<1>, and an area assigned to a second videotitle set VTS<2>. The video manager VMG contains video managerinformation VMGI for managing the video title sets VTS<1> and VTS<2>.Each of the video title sets VTS<1> and VTS<2> has a sequence of packsincluding video packs V and audio packs A.

The ANV-TS_D area in FIG. 28 has an area assigned to an audio managerAMG, an area assigned to a first audio title set ATS<1>, and an areaassigned to a second audio title set ATS<2>. The audio manager AMGcontains audio manager information AMGI for managing the audio titlesets ATS<1> and ATS<2>. The audio manager AMG has a structure similar tothat in FIG. 3. Each of the audio title sets ATS<1> and ATS<2> has asequence of packs including audio packs A. The first audio title setATS<1> forms a pair with the first video title set VTS<1>. The secondaudio title set ATS<2> forms a pair with the second video title setVTS<2>.

FIG. 29 shows the signal recording format of a DVD-Video (digital videodisc-video). The DVD-Video in FIG. 29 has an area assigned to a videotitle set directory VTS_D. The video title set VTS corresponds to DVDvideo data. The video title set VTS has a structure similar to that inFIG. 1. The DVD-Video in FIG. 29 does not have any area assigned to anaudio title set directory ATS_D. The DVD-Video in FIG. 29 does not haveany area assigned to an audio navigation title set directory ANV-TS_D.

The VTS_D area in FIG. 29 has an area assigned to a video manager VMG,an area assigned to a video manager menu VMGM, an area assigned to afirst video title set VTS<1>, and an area assigned to a second videotitle set VTS<2>. The video manager VMG contains video managerinformation VMGI for managing the video title sets VTS<1> and VTS<2>.Each of the video title sets VTS<L> and VTS<2> has a sequence of packsincluding video packs V and audio packs A.

FIG. 30 shows the signal recording format of a DVD-Avd (digital videodisc-audio plus AV data). The DVD-Avd in FIG. 30 has an area assigned toa video title set directory VTS_D, and an area assigned to an audiotitle set directory ATS_D. The video title set VTS corresponds to DVDvideo data while the audio title set ATS corresponds to DVD audio data.The video title set VTS has a structure similar to that in FIG. 1.

The VTS_D area in FIG. 30 has an area assigned to a video manager VMG,an area assigned to a video manager menu VMGM, and an area assigned to avideo title set VTS<1>. The video manager VMG contains video managerinformation VMGI for managing the video title set VTS<1>. The videotitle set VTS<1>has a sequence of packs including video packs V andaudio packs A.

The ATS_D area in FIG. 30 has an area assigned to an audio manager AMG,an area assigned to an audio manager menu AMGM, an area assigned to afirst audio title set ATS<1>, and an area assigned to a second audiotitle set ATS<2>. The audio manager AMG contains audio managerinformation AMGI for managing the audio title sets ATS<1> and ATS<2>.The audio manager AMG has a structure similar to that in FIG. 3. Thefirst audio title set ATS<1> has a sequence of packs including audiopacks A. The first audio title set ATS<1> forms a pair with the videotitle set VTS<1>. The second audio title set ATS<2> has a sequence ofpacks including audio packs A, still-picture packs SPCT, and real-timeinformation packs RTI. The pack sequence in the second audio title setATS<2> does not have any audio control pack A-CONT.

Each of the audio title sets ATS<1> and ATS<2> in the DVD-Audio of FIG.26 contains audio title set information ATSI. The audio title setinformation ATSI contains a management table ATSI-MAT having anaudio-only-title audio-object attribute AOTT-AOB-ATR.

As shown in FIG. 31, the audio-only-title audio-object attributeAOTT-AOB-ATR has a sequence of 16 bytes, that is, 128 bits b127, b126,b125, . . . , b1, b0. A set of the bits b127, b126, b125, b124, b123,b122, b121, and b120 represents an audio encoding mode. A set of thebits b111, b110, b109, and b108 represents a quantization bit number Q1of a channel group “1”. A set of the bits b107, b106, b105, and b104represents a quantization bit number Q2 of a channel group “2”. A set ofthe bits b103, b102, b101, and b100 represents a sampling frequency fs1of the channel group “1”. A set of the bits b99, b98, b97, and b96represents a sampling frequency fs2 of the channel group “2”. A set ofthe bits b95, b94, and b93 represents a multiple channel type. A set ofthe bits b92, b91, b90, b89, and b88 represents channel assignment. Theother bits form reserved areas.

The audio encoding mode represented by the bits b127, b126, b125, b124,b123, b122, b121, and b120 in FIG. 31 can be selected from among alinear PCM audio encoding mode, a Dolby digital encoding mode, an MPEG-2encoding mode without any extension, an MPEG-2 encoding mode with anextension, a DTS encoding mode, and an SDDS encoding mode. Specifically,a bit sequence of “00000000” is assigned to the linear PCM audioencoding mode. A bit sequence of “00000001” is assigned to the Dolbydigital encoding mode. A bit sequence of “00000010” is assigned to theMPEG-2 encoding mode without any extension. A bit sequence of “00000011”is assigned to the MPEG-2 encoding mode with an extension. A bitsequence of “00000100” is assigned to the DTS encoding mode. A bitsequence of “00000101” is assigned to the SDDS encoding mode.

The quantization bit number Q1 of the channel group “1” which isrepresented by the bits b111, b110, b109, and b108 in FIG. 31 can bechanged among 16 bits, 20 bits, and 24 bits. Specifically, a bitsequence of “0000” is assigned to 16 bits. A bit sequence of “0001” isassigned to 20 bits. A bit sequence of “0010” is assigned to 20 bits.

The quantization bit number Q2 of the channel group “2” which isrepresented by the bits b107, b106, b105, and b104 in FIG. 31 can bechanged among 16 bits, 20 bits, and 24 bits. Specifically, a bitsequence of “0000” is assigned to 16 bits. A bit sequence of “0001” isassigned to 20 bits. A bit sequence of “0010” is assigned to 20 bits.

The state of the set of the bits b107, b106, b105, and b104 has thefollowing relation with the state of the set of the bits b111, b110,b109, and b108. When the set of the bits b111, b110, b109, and b108 is“0000”, the set of the bits b107, b106, b105, and b104 is also “0000”.In other words, when the quantization bit number Q1 for the channelgroup “1” is equal to 16 bits, the quantization bit number Q2 for thechannel group “2” is also equal to 16 bits. When the set of the bitsb111, b110, b109, and b108 is “0001”, the set of the bits b107, b106,b105, and b104 is “0000” or “0001. In other words, when the quantizationbit number Q1 for the channel group “1” is equal to 20 bits, thequantization bit number Q2 for the channel group “2” is equal to 16 bitsor 20 bits. When the set of the bits b111, b110, b109, and b108 is“0010”, the set of the bits b107, b106, b105, and b104 is “0000”, “0001,or “0010”. In other words, when the quantization bit number Q1 for thechannel group “1” is equal to 24 bits, the quantization bit number Q2for the channel group “2” is equal to 16 bits, 20 bits, or 24 bits.

The sampling frequency fs1 of the channel group “1” which is representedby the bits b103, b102, b101, and b100 can be changed among 48 kHz, 96kHz, 192 kHz, 44.1 kHz, 88.2 kHz, and 176.4 kHz. Specifically, a bitsequence of “0000” is assigned to 48 kHz. A bit sequence of “0001” isassigned to 96 kHz. A bit sequence of “0010” is assigned to 192 kHz. Abit sequence of “1000” is assigned to 44.1 kHz. A bit sequence of “1001”is assigned to 88.2 kHz. A bit sequence of “1010” is assigned to 176.4kHz.

The sampling frequency fs2 of the channel group “2” which is representedby the bits b99, b98, b97, and b96 can be changed among 48 kHz, 96 kHz,192 kHz, 44.1 kHz, 88.2 kHz, and 176.4 kHz. Specifically, a bit sequenceof “0000” is assigned to 48 kHz. A bit sequence of “0001” is assigned to96 kHz. A bit sequence of “0010” is assigned to 192 kHz. A bit sequenceof “1000” is assigned to 44.1 kHz. A bit sequence of “1001” is assignedto 88.2 kHz. A bit sequence of “1010” is assigned to 176.4 kHz.

The state of the set of the bits b99, b98, b97, and b96 has thefollowing relation with the state of the set of the bits b103, b102,b101, and b100. When the set of the bits b103, b102, b101, and b100 is“0000”, the set of the bits b99, b98, b97, and b96 is also “0000”. Inother words, when the sampling frequency “fs” of the channel group “1”is equal to 48 kHz, the sampling frequency “fs” of the channel group “2”is also equal to 48 kHz. When the set of the bits b103, b102, b101, andb100 is “0001”, the set of the bits b99, b98, b97, and b96 is “0000” or“0001”. In other words, when the sampling frequency “fs” of the channelgroup “1” is equal to 96 kHz, the sampling frequency “fs” of the channelgroup “2” is equal to 48 kHz or 96 kHz. When the set of the bits b103,b102, b101, and b100 is “0010”, the set of the bits b99, b98, b97, andb96 is “0000”, “0001”, or “0010”. In other words, when the samplingfrequency “fs” of the channel group “1” is equal to 192 kHz, thesampling frequency “fs” of the channel group “2” is equal to 48 kHz, 96kHz, or 192 kHz. When the set of the bits b103, b102, b101, and b100 is“1000”, the set of the bits b99, b98, b97, and b96 is also “1000”. Inother words, when the sampling frequency “fs” of the channel group “1”is equal to 44.1 kHz, the sampling frequency “fs” of the channel group“2” is also equal to 44.1 kHz. When the set of the bits b103, b102,b101, and b100 is “1001”, the set of the bits b99, b98, b97, and b96 is“1000” or “1001”. In other words, when the sampling frequency “fs” ofthe channel group “1” is equal to 88.2 kHz, the sampling frequency “fs”of the channel group “2” is equal to 44.1 kHz or 88.2 kHz. When the setof the bits b103, b102, b101, and b100 is “1010”, the set of the bitsb99, b98, b97, and b96 is “1000”, “1001”, or “1010”. In other words,when the sampling frequency “fs” of the channel group “1” is equal to176.4 kHz, the sampling frequency “fs” of the channel group “2” is equalto 44.1 kHz, 88.2 kHz, or 176.4 kHz.

Normally, the bits b95, b94, and b93 in FIG. 31 are set to “000”representing that the multiple channel type agrees with a type “1”.

The channel assignment represented by the bits b92, b91, b90, b89, andb88 in FIG. 31 can be changed among 21 different types shown in FIG. 32.A bit sequence of “00000” is assigned to a first type of the channelassignment in which a first channel ACH0 forms a monaural channelC(mono), and second and later channels ACH1, ACH2, ACH3, ACH4, and ACH5are unused. According to the first type of the channel assignment, themonaural channel C(mono) is in the group “1”. Thus, the channel numberin the group “1” is equal to one while the channel number in the group“2” is equal to zero. A bit sequence of “00001” is assigned to a secondtype of the channel assignment in which the first and second channelsACH0 and ACH1 form a left channel L and a right channel R respectively,and the third and later channels ACH2, ACH3, ACH4, and ACH5 are unused.According to the second type of the channel assignment, the left channelL and the right channel R are in the group “1”. Thus, the channel numberin the group “1” is equal to two while the channel number in the group“2” is equal to zero. A bit sequence of “00010” is assigned to a thirdtype of the channel assignment in which the first, second, and thirdchannels ACH0, ACH1, and ACH2 form a left front channel Lf, a rightfront channel Rf, and a surround channel S respectively, and the fourthand later channels ACH3, ACH4, and ACH5 are unused. According to thethird type of the bit assignment, the left front channel Lf and theright front channel Rf are in the group “1” while the surround channel Sis in the group “2”. Thus, the channel number in the group “1” is equalto two while the channel number in the group “2” is equal to one. A bitsequence of “00011” is assigned to a fourth type of the channelassignment in which the first, second, third, and fourth channels ACH0,ACH1, ACH2, and ACH3 form a left front channel Lf, a right front channelRf, a left surround channel Ls, and a right surround channel Rsrespectively, and the fifth and sixth channels ACH4 and ACH5 are unused.According to the fourth type of the channel assignment, the left frontchannel Lf and the right front channel Rf are in the group “1” while theleft surround channel Ls and the right surround channel Rs are in thegroup “2”. Thus, the channel number in the group “1” is equal to twowhile the channel number in the group “2” is also equal to two. A bitsequence of “00100” is assigned to a fifth type of the channelassignment in which the first, second, and third channels ACH0, ACH1,and ACH2 form a left front channel Lf, a right front channel Rf, and alow frequency effect channel LFE respectively, and the fourth and laterchannels ACH3, ACH4, and ACH5 are unused. According to the fifth type ofthe channel assignment, the left front channel Lf and the right frontchannel Rf are in the group “1” while the low frequency effect channelLFE is in the group “2”. Thus, the channel number in the group “1” isequal to two while the channel number in the group “2” is equal to one.A bit sequence of “00101” is assigned to a sixth type of the channelassignment in which the first, second, third, and fourth channels ACH0,ACH1, ACH2, and ACH3 form a left front channel Lf, a right front channelRf, a low frequency effect channel LFE, and a surround channel Srespectively, and the fifth and sixth channels ACH4 and ACH5 are unused.According to the sixth type of the channel assignment, the left frontchannel Lf and the right front channel Rf are in the group “1” while thelow frequency effect channel LFE and the surround channel S are in thegroup “2”. Thus, the channel number in the group “1” is equal to twowhile the channel number in the group “2” is also equal to two. A bitsequence of “00110” is assigned to a seventh type of the channelassignment in which the first, second, third, fourth, and fifth channelsACH0, ACH1, ACH2, ACH3, and ACH4 form a left front channel Lf, a rightfront channel Rf, a low frequency effect channel LFE, a left surroundchannel Ls, and a right surround channel Rs respectively, and the sixthchannel ACH5 is unused. According to the seventh type of the channelassignment, the left front channel Lf and the right front channel Rf arein the group “1” while the low frequency effect channel LFE, the leftsurround channel Ls, and the right surround channel Rs are in the group“2”. Thus, the channel number in the group “1” is equal to two while thechannel number in the group “2” is equal to three. A bit sequence of“00111” is assigned to an eighth type of the channel assignment in whichthe first, second, and third channels ACH0, ACH1, and ACH2 form a leftfront channel Lf, a right front channel Rf, and a center channel Crespectively, and the fourth and later channels ACH3, ACH4, and ACH5 areunused. According to the eighth type of the channel assignment, the leftfront channel Lf and the right front channel Rf are in the group “1”while the center channel C is in the group “2”. Thus, the channel numberin the group “1” is equal to two while the channel number in the group“2” is equal to one. A bit sequence of “01000” is assigned to a ninthtype of the channel assignment in which the first, second, third, andfourth channels ACH0, ACH1, ACH2, and ACH3 form a left front channel Lf,a right front channel Rf, a center channel C, and a surround channel Srespectively, and the fifth and sixth channels ACH4 and ACH5 are unused.According to the ninth type of the channel assignment, the left frontchannel Lf and the right front channel Rf are in the group “1” while thecenter channel C and the surround channel S are in the group “2”. Thus,the channel number in the group “1” is equal to two while the channelnumber in the group “2” is also equal to two. A bit sequence of “01001”is assigned to a tenth type of the channel assignment in which thefirst, second, third, fourth, and fifth channels ACH0, ACH1, ACH2, ACH3,and ACH4 form a left front channel Lf, a right front channel Rf, acenter channel C, a left surround channel Ls, and a right surroundchannel Rs respectively, and the sixth channel ACH5 is unused. Accordingto the tenth type of the channel assignment, the left front channel Lfand the right front channel Rf are in the group “1” while the centerchannel C, the left surround channel Ls, and the right surround channelRs are in the group “2”. Thus, the channel number in the group “1” isequal to two while the channel number in the group “2” is equal tothree. A bit sequence of “01010” is assigned to an eleventh type of thechannel assignment in which the first, second, third, and fourthchannels ACH0, ACH1, ACH2, and ACH3 form a left front channel Lf, aright front channel Rf, a center channel C, and a low frequency effectchannel LFE respectively, and the fifth and sixth channels ACH4 and ACH5are unused. According to the eleventh type of the channel assignment,the left front channel Lf and the right front channel Rf are in thegroup “1” while the center channel C and the low frequency effectchannel LFE are in the group “2”. Thus, the channel number in the group“1” is equal to two while the channel number in the group “2” is alsoequal to two. A bit sequence of “00101” is assigned to a twelfth type ofthe channel assignment in which the first, second, third, fourth, andfifth channels ACH0, ACH1, ACH2, ACH3, and ACH4 form a left frontchannel Lf, a right front channel Rf, a center channel C, a lowfrequency effect channel LFE, and a surround channel S respectively, andthe sixth channel ACH5 is unused. According to the twelfth type of thechannel assignment, the left front channel Lf and the right frontchannel Rf are in the group “1” while the center channel C, the lowfrequency effect channel LFE, and the surround channel S are in thegroup “2”. Thus, the channel number in the group “1” is equal to twowhile the channel number in the group “2” is equal to three. A bitsequence of “01100” is assigned to a thirteenth type of the channelassignment in which the first, second, third, fourth, fifth, and sixthchannels ACH0, ACH1, ACH2, ACH3, ACH4, and ACH5 form a left frontchannel Lf, a right front channel Rf, a center channel C, a lowfrequency effect channel LFE, a left surround signal Ls, and a rightsurround channel Rs respectively. According to the thirteenth type ofthe channel assignment, the left front channel Lf and the right frontchannel Rf are in the group “1” while the center channel C, the lowfrequency effect channel LFE, the left surround signal Ls, and the rightsurround channel Rs are in the group “2”. Thus, the channel number inthe group “1” is equal to two while the channel number in the group “2”is equal to four. A bit sequence of “01101” is assigned to a fourteenthtype of the channel assignment in which the first, second, third, andfourth channels ACH0, ACH1, ACH2, and ACH3 form a left front channel Lf,a right front channel Rf, a center channel C, and a surround channel Srespectively, and the fifth and sixth channels ACH4 and ACH5 are unused.According to the fourteenth type of the channel assignment, the leftfront channel Lf, the right front channel Rf, and the center channel Care in the group “1” while the surround channel S is in the group “2”.Thus, the channel number in the group “1” is equal to three while thechannel number in the group “2” is equal to one. A bit sequence of“01110” is assigned to a fifteenth type of the channel assignment inwhich the first, second, third, fourth, and fifth channels ACH0, ACH1,ACH2, ACH3, and ACH4 form a left front channel Lf, a right front channelRf, a center channel C, a left surround channel Ls, and a right surroundchannel Rs respectively, and the sixth channel ACH5 is unused. Accordingto the fifteenth type of the channel assignment, the left front channelLf, the right front channel Rf, and the center channel C are in thegroup “1” while the left surround channel Ls and the right surroundchannel Rs are in the group “2”. Thus, the channel number in the group“1” is equal to three while the channel number in the group “2” is equalto two. A bit sequence of “01111” is assigned to a sixteenth type of thechannel assignment in which the first, second, third, and fourthchannels ACH0, ACH1, ACH2, and ACH3 form a left front channel Lf, aright front channel Rf, a center channel C, and a low frequency effectchannel LFE respectively, and the fifth and sixth channels ACH4 and ACH5are unused. According to the sixteenth type of the channel assignment,the left front channel Lf, the right front channel Rf, and the centerchannel C are in the group “1” while the low frequency effect channelLFE is in the group “2”. Thus, the channel number in the group “1” isequal to three while the channel number in the group “2” is equal toone. A bit sequence of “10000” is assigned to a seventeenth type of thechannel assignment in which the first, second, third, fourth, and fifthchannels ACH0, ACH1, ACH2, ACH3, and ACH4 form a left front channel Lf,a right front channel Rf, a center channel C, a low frequency effectchannel LFE, and a surround channel S respectively, and the sixthchannel ACH5 is unused. According to the seventeenth type of the channelassignment, the left front channel Lf, the right front channel Rf, andthe center channel C are in the group “1” while the low frequency effectchannel LFE and the surround channel S are in the group “2”. Thus, thechannel number in the group “1” is equal to three while the channelnumber in the group “2” is equal to two. A bit sequence of “10001” isassigned to an eighteenth type of the channel assignment in which thefirst, second, third, fourth, fifth, and sixth channels ACH0, ACH1,ACH2, ACH3, ACH4, and ACH5 form a left front channel Lf, a right frontchannel Rf, a center channel C, a low frequency effect channel LFE, aleft surround signal Ls, and a right surround channel Rs respectively.According to the eighteenth type of the channel assignment, the leftfront channel Lf, the right front channel Rf, and the center channel Care in the group “1” while the low frequency effect channel LFE, theleft surround signal Ls, and the right surround channel Rs are in thegroup “2”. Thus, the channel number in the group “1” is equal to threewhile the channel number in the group “2” is also equal to three. A bitsequence of “10010” is assigned to a nineteenth type of the channelassignment in which the first, second, third, fourth, and fifth channelsACH0, ACH1, ACH2, ACH3, and ACH4 form a left front channel Lf, a rightfront channel Rf, a left surround channel Ls, a right surround channelRs, and a low frequency effect channel LFE respectively, and the sixthchannel ACH5 is unused. According to the nineteenth type of the channelassignment, the left front channel Lf, the right front channel Rf, theleft surround channel Ls, and the right surround channel Rs are in thegroup “1” while the low frequency effect channel LFE is in the group“2”. Thus, the channel number in the group “1” is equal to four whilethe channel number in the group “2” is equal to one. A bit sequence of“10011” is assigned to a twentieth type of the channel assignment inwhich the first, second, third, fourth, and fifth channels ACH0, ACH1,ACH2, ACH3, and ACH4 form a left front channel Lf, a right front channelRf, a left surround channel Ls, a right surround channel Rs, and acenter channel C respectively, and the sixth channel ACH5 is unused.According to the twentieth type of the channel assignment, the leftfront channel Lf, the right front channel Rf, the left surround channelLs, and the right surround channel Rs are in the group “1” while thecenter channel C is in the group “2”. Thus, the channel number in thegroup “1” is equal to four while the channel number in the group “2” isequal to one. A bit sequence of “10100” is assigned to a twenty-firsttype of the channel assignment in which the first, second, third,fourth, fifth, and sixth channels ACH0, ACH1, ACH2, ACH3, ACH4, and ACH5form a left front channel Lf, a right front channel Rf, a left surroundchannel Ls, a right surround channel Rs, a center channel C, and a lowfrequency effect channel LFE respectively. According to the twenty-firsttype of the channel assignment, the left front channel Lf, the rightfront channel Rf, the left surround channel Ls, and the right surroundchannel Rs are in the group “1” while the center channel C and the lowfrequency effect channel C are in the group “2”. Thus, the channelnumber in the group “1” is equal to four while the channel number in thegroup “2” is equal to two.

Normally, in the DVD-Audio of FIG. 26, the audio encoding moderepresented by the bits b127, b126, b125, b124, b123, b122, b121, andb120 in FIG. 31 agrees with the linear PCM audio encoding mode.According to the linear PCM audio encoding mode, every audio pack A has2,048 bytes or less.

As shown in FIG. 33, a linear PCM audio pack A has a 14-byte pack headerand an audio packet. The pack header is followed by the audio packet.The audio packet has a sequence of a packet header, a private header,and audio data. The packet header has 9 bytes, 14 bytes, or 17 bytes.The audio data has 1 byte to 2,013 bytes.

As shown in FIGS. 33 and 34, the private header has a sequence of 8-bitsub stream ID (identification) information, a 4-bit reserved area, 4-bitinformation of an ISRC number, 8-bit information of ISRC data, 8-bitinformation of the private header length, a 16-bit first access unitpointer, 6-byte audio data information ADI, and 0 to 7 stuffing bytes.

As shown in FIG. 34, the audio data information ADI (see FIG. 33) has asequence of a 1-bit audio emphasis flag, a 1-bit reserved area, a 2-bitreserved area, a 4-bit down mix code, 4-bit information of thequantization word length (the quantization bit number) in the group “1”,4-bit information of the quantization word length (the quantization bitnumber) in the group “2”, 4-bit information of the audio samplingfrequency fs1 in the group “1”, 4-bit information of the audio samplingfrequency fs2 in the group “2”, a 4-bit reserved area, 4-bit informationof a multiple channel type, a 3-bit reserved area, 5-bit channelassignment information (see FIG. 32), and 8-bit dynamic-range controlinformation.

The audio-only-title audio-object attribute AOTT-AOB-ATR in FIG. 31 maybe replaced by an audio-only-title video-object audio-stream attributeAOTT-VOB-AST-ATR when used in VTS_D in FIG. 30. The audio-only-titlevideo-object audio-stream attribute AOTT-VOB-AST-ATR has a structureshown in FIG. 35.

Third Embodiment

FIG. 36 shows an audio-signal encoding apparatus according to a thirdembodiment of this invention. The apparatus of FIG. 36 includesanalog-to-digital (A/D) converters 31 and 31V, a signal processingcircuit 32, a video encoder 32V, and a DVD formatting section 34.

An analog video signal is applied to the A/D converter 31V. The A/Dconverter 31V is followed by the video encoder 32V. The video encoder32V is followed by the DVD formatting section 34.

An analog audio signal is applied to the A/D converter 31. In general,the analog audio signal has multiple channels including, for example,front and rear channels. The analog audio signal may be of the monauraltype. The A/D converter 31 is followed by the signal processing circuit32. The signal processing circuit 32 is followed by the DVD formattingsection 34.

The DVD formatting section 34 is successively followed by a modulationcircuit 35A and a master making apparatus 35B.

As shown in FIG. 37, the signal processing circuit 32 includes a lowpass filter (LPF) 36, thinning circuits (decimating circuits) 37 and 38,a subtracter 39, and an allocation circuit 40. The low pass filter 36,the thinning circuit 38, and the allocation circuit 40 follow the A/Dconverter 31 (see FIG. 36). The low pass filter 36 is followed by thethinning circuit 37. A first input terminal of the subtracter 39 isconnected to the output terminal of the thinning circuit 37. A secondinput terminal of the subtracter 39 is connected to the output terminalof the thinning circuit 38. The output terminal of the subtracter 39 isconnected to the allocation circuit 40. The output terminal of thethinning circuit 37 is connected to the allocation circuit 40. Theallocation circuit 40 is followed by the DVD formatting section 34 (seeFIG. 36).

The A/D converter 31 samples the analog audio signal at a given samplingfrequency “fs”, and changes every sample of the analog audio signal intoa corresponding digital sample. Thus, the A/D converter 31 changes theanalog audio signal into a corresponding digital audio signal (forexample, a PCM audio signal) with a given quantization bit number. Inother words, the A/D converter 31 quantizes the analog audio signal intothe corresponding digital audio signal. The quantization implemented bythe A/D converter 31 may vary from channel to channel. For example, theA/D converter 31 quantizes front-channel components of the analog audiosignal at a first predetermined sampling frequency and a firstpredetermined quantization bit number. The A/D converter 31 quantizesrear-channel components of the analog audio signal at a secondpredetermined sampling frequency and a second predetermined bit numberwhich are equal to or different from the first predetermined samplingfrequency and the first predetermined quantization bit numberrespectively. The A/D converter 31 outputs the digital audio signal tothe signal processing circuit 32.

Operation of the signal processing circuit 32 can be changed betweenfirst and second modes which correspond to the absence and the presenceof thinning respectively.

During operation of the signal processing circuit 32 in the first mode(the absence of thinning), the digital audio signal is directlytransmitted from the A/D converter 31 to the allocation circuit 40. Thedevice 40 allocates the digital audio signal to audio data which can beplaced in audio packs A (see FIG. 14 or FIG. 33). The allocation circuit40 outputs the audio data to the DVD formatting section 34.

During operation of the signal processing circuit 32 in the second mode(the presence of thinning), the digital audio signal is transmitted fromthe A/D converter 31 to the low pass filter 36 and the thinning circuit38. The low pass filter 36 conducts only a half of the frequency band ofthe digital audio signal. The low pass filter 36 outputs the resultantsignal to the thinning circuit 37. The thinning circuit 37 selects onefourth of samples of the output signal of the low pass filter 36. Thethinning circuit 37 outputs only the selected signal samples to thesubtracter 39 and the allocation circuit 40. The selected samples arespaced at 4-sample intervals.

During operation of the signal processing circuit 32 in the second mode(the presence of thinning), the thinning circuit 38 selects alternateones of samples of the digital audio signal. The thinning circuit 38outputs only the selected signal samples to the subtracter 39.

A sequence of samples of the output signal from the thinning circuit 37is now expressed as:

xc1, xc2, xc3, . . . , xci, . . .

On the other hand, a sequence of samples of the output signal from thethinning circuit 38 is expressed as:

xb1, xa1, xb2, xa2, . . . , xbi, xai, . . .

During operation of the signal processing circuit 32 in the second mode(the presence of thinning), the subtracter 39 calculates differences Δ1i and Δ2 i between the output signals of the thinning circuits 37 and38. The differences Δ1 i and Δ2 i are given as follows.Δ1 i=xbi−xciΔ2 i=xai−xciThe subtracter 39 informs the allocation circuit 40 of the calculateddifferences Δ1 i and Δ2 i.

During operation of the signal processing circuit 32 in the second mode(the presence of thinning), the allocation circuit 40 combines theoutput signal of the thinning circuit 37 and the information of thedifferences Δ1 i and Δ2 i into audio user data which can be placed inaudio packs A (see FIG. 14 or FIG. 33). The allocation circuit 40outputs the audio user data to the DVD formatting section 34.

The A/D converter 31V changes the analog video signal into acorresponding digital video signal. The A/D converter 31V outputs thedigital video signal to the video encoder 32V. The video encoder 32Vchanges the digital video signal into an MPEG-format signal. The videoencoder 32V packs the MPEG-format signal into video user data which canbe placed in video packs V. The video encoder 32V outputs the video userdata to the DVD formatting section 34.

The DVD formatting section 34 receives control data from suitabledevices (not shown). The control data represents character information,display time information, sampling-frequency information,quantization-bit-number information, thinning information, and otherinformation to be added. The DVD formatting section 34 packs the audiodata (or the audio user data), the video user data, and the addedinformation into a composite signal of a DVD-Audio format correspondingto the signal recording format of the DVD-Audio in FIG. 2 or the signalrecording format of the DVD-Audio in FIG. 26. The DVD formatting section34 outputs the composite signal of the DVD-Audio format to themodulation circuit 35A. The modulation circuit 35A subjects thecomposite signal of the DVD-Audio format to given modulation (forexample, EFM modulation) suited to a DVD-Audio. The modulation circuit35A outputs the modulation-resultant signal to the master makingapparatus 35B. The apparatus 35B makes a master disc 35C in response tothe output signal of the modulation circuit 35A. The maser disc 35Cstores the output signal of the modulation circuit 35A. DVD-Audios aremade by a DVD making apparatus (not shown) on the basis of the masterdisc 35C.

Fourth Embodiment

FIG. 38 shows a DVD-Audio player including an audio-signal decodingapparatus according to a fourth embodiment of this invention. The playerin FIG. 38 is designed for a DVD-Audio in FIG. 2.

The player in FIG. 38 operates on a DVD-Audio 1. The player in FIG. 38includes an operation unit 18 and a remote control unit 19. The remotecontrol unit 19 can communicate with the operation unit 18 by wireless.The operation unit 18 is connected to a control unit 23 including a CPU.The control unit 23 is connected to a drive unit 2 and a reproducedsignal processing unit 17. The drive unit 2 is connected to thereproduced signal processing unit 17.

The CPU 23 operates in accordance with a program stored in an internalROM. When the user actuates the operation unit 18 or the remote controlunit 19 to request tune selection, playback, fast feed, or stop, the CPU23 controls the drive unit 2 and the reproduced signal processing unit17 to implement the requested operation mode.

During playback, the drive unit 2 reads out a signal from the DVD-Audio1. The drive unit 2 includes a demodulator which subjects the readoutsignal to given demodulation (for example, EFM demodulation). The driveunit 2 outputs the demodulation-resultant signal to the reproducedsignal processing unit 17 as a reproduced signal. The drive unit 2 has afunction of detecting TOC information in the demodulation-resultantsignal (the reproduced signal). The drive unit 2 outputs the detectedTOC information to the signal processing unit 17.

The reproduced signal processing circuit 17 includes a control packdetector 3 which receives the reproduced signal from the drive unit 2.The control pack detector 3 detects every control pack CONT in thereproduced signal. The control pack detector 3 generates controlparameters in response to the detected control pack CONT. The controlpack detector 3 sets the control parameters in a parameter unit (aparameter memory) 8. The control pack detector 3 selects video packs Vfrom the reproduced signal in response to the detected control packCONT. The control pack detector 3 sequentially writes the video packs Vinto a video pack buffer 4.

The reproduced signal processing circuit 17 includes a reading unit 5connected to the video pack buffer 4. The reading unit 5 reads out userdata from the video packs V in the video pack buffer 4 in an orderdetermined by SCR information (see FIG. 14) in each of the video packsV. The reading unit 5 outputs a stream of the user data to a pictureconverter 6. The picture converter 6 changes the user data stream into acorresponding digital video signal. The picture converter 6 outputs thedigital video signal to a digital-to-analog (D/A) converter 7. The D/Aconverter 7 changes the digital video signal into a corresponding analogvideo signal. The D/A converter 7 outputs the analog video signal to anexternal device (not shown).

It should be noted that the reading unit 5 may read out user data fromthe video packs V in the video pack buffer 4 in an order determined byPTS (presentation time stamp) information in a control pack CONT. Tothis end, the control pack detector 3 feeds the PTS information in thedetected control pack CONT to the reading unit 5.

The reproduced signal processing circuit 17 includes an audio controlpack detector 9 which receives the reproduced signal from the drive unit2. The audio control pack detector 9 detects every audio control packA-CONT in the reproduced signal. The audio control pack detector 9generates control parameters in response to the detected audio controlpack A-CONT. The audio control pack detector 9 sets the controlparameters in a parameter unit (a parameter memory) 14. The audiocontrol pack detector 9 selects audio packs A from the reproduced signalin response to the detected audio control pack A-CONT. The audio controlpack detector 9 sequentially writes the audio packs A into an audio packbuffer 10.

The reproduced signal processing circuit 17 includes a reading unit 11connected to the audio pack buffer 10. The reading unit 11 reads outuser data (audio data) from the audio packs A in the audio pack buffer10 in an order determined by SCR information (see FIG. 14) in each ofthe audio packs A. The reading unit 11 outputs a stream of the user data(the audio data) to a PCM converter 12. The PCM converter 12 changes theuser data stream (the audio data stream) into a corresponding digitalaudio signal by a PCM decoding process. The PCM converter 12 outputs thedigital audio signal to a digital-to-analog (D/A) converter 13. The D/Aconverter 13 changes the digital audio signal into a correspondinganalog audio signal. The analog audio signal has, for example a leftfront channel Lf, a right front channel Rf, a center channel C, a leftsurround channel Ls, and a right surround channel Rs. The D/A converter13 outputs the analog audio signal to an external device (not shown).

It should be noted that the reading unit 11 may read out user data(audio data) from the audio packs A in the audio pack buffer 10 in anorder determined by present-time information in audio search data ASD(see FIG. 18) in an audio control pack A-CONT. To this end, the audiocontrol pack detector 9 feeds the present-time information in thedetected audio control pack A-CONT to the reading unit 11.

The reproduced signal processing unit 17 includes a memory 14A whichstores the TOC information fed from the drive unit 2. The memory 14A isconnected to the parameter units 8 and 14, and the control unit 23. Whenthe user actuates the operation unit 18 or the remote control unit 19 toselect a desired tune, the control unit 23 refers to the TOC informationin the memory 14A and controls the drive unit 2 and the reproducedsignal processing unit 17 in response to the TOC information to startplayback of the desired tune from its head.

The reproduced signal processing unit 17 includes a detector 95 whichreceives the reproduced signal from the drive unit 2. The detector 95extracts information of sampling frequencies “fs” (fs1 and fs2) andinformation of quantization bit numbers Q (Q1 and Q2) from thereproduced signal. The detector 95 feeds the information of the samplingfrequencies “fs” (fs1 and fs2) and the information of the quantizationbit numbers Q (Q1 and Q2) to the CPU 23. The CPU 23 controls the PCMconverter 12 and the D/A converter 13 in response to the information ofthe sampling frequencies “fs” (fs1 and fs2) and the information of thequantization bit numbers Q (Q1 and Q2). Accordingly, conditions of theinverse quantization (the signal decoding) implemented by the PCMconverter 12 and the D/A converter 13 depend on the information of thesampling frequencies “fs” (fs1 and fs2) and the information of thequantization bit numbers Q (Q1 and Q2). Thus, the inverse quantizationcan be on a channel by channel basis or a channel-group by channel-groupbasis.

Fifth Embodiment

FIG. 39 shows a DVD-Audio player including an audio-signal decodingapparatus according to a fifth embodiment of this invention. The playerin FIG. 39 is basically similar to the player in FIG. 38.

The player in FIG. 39 operates on a DVD-Audio 1 which has a TOC area 1 aloaded with TOC information. The TOC area 1 a may be omitted from theDVD-Audio 1. The player in FIG. 39 includes a control unit 23 connectedto an operation unit (not shown). The control unit 23 includes a CPU. Aremote control unit (not shown) can communicate with the operation unitby wireless. The control unit 23 is connected to a reproducing device2A.

The reproducing device 2A is connected to a TOC detector 2B, an audioprocessor 17A, and a video processor 17B. The TOC detector 2B isconnected to a memory 14A. The memory 14A is connected to the controlunit 23. The audio processor 17A and the video processor 17B areconnected to the control unit 23. The audio processor 17A is connectedto output devices 13A and 13B. The video processor 17B is connected tooutput devices 7A and 7B.

When the DVD-Audio 1 is set in position within the player of FIG. 39,the reproducing device 2A reads out a signal from the TOC area 1 a ofthe DVD-Audio 1. The reproducing device 2A outputs the readout signal tothe TOC detector 2B. The TOC detector 2B detects TOC information in thereadout signal. The TOC detector 2B stores the detected TOC informationinto the memory 14A.

When the user actuates the operation unit or the remote control unit toselect a desired tune, the control unit 23 refers to the TOC informationin the memory 14A and controls the reproducing device 2A in response tothe TOC information to start playback of the desired tune from its head.

During playback, the reproducing device 2A reads out a signal from theDVD-Audio 1. The reproducing device 2A outputs the readout signal to theaudio processor 17A and the video processor 17B as a reproduced signal.The audio processor 17A separates audio data from the reproduced signal.The audio processor 17A feeds the audio data to the output device 13A.The output device 13A converts the audio data into a corresponding audiosignal. The output device 13A feeds the audio signal to an externaldevice (not shown). In addition, the audio processor 17A separatescharacter information from the reproduced signal. The audio processor17A feeds the character information to the output device 13B. The outputdevice 13B converts the character information into a correspondingcharacter signal. The output device 13B feeds the character signal to anexternal device (not shown). Furthermore, the audio processor 17Aseparates information in every audio control pack A-CONT from thereproduced signal. The audio processor 17A feeds the audio control packinformation to the control unit 23.

During playback, the video processor 17B separates video data from thereproduced signal. The video processor 17B feeds the video data to theoutput device 7A. The output device 7A converts the video data into acorresponding video signal. The output device 7A feeds the video signalto an external device (not shown). In addition, the video processor 17Bseparates sub picture information from the reproduced signal. The videoprocessor 17B feeds the sub picture information to the output device 7B.The output device 7B converts the sub picture information into acorresponding sub picture signal. The output device 7B feeds the subpicture signal to an external device (not shown). Furthermore, the videoprocessor 17B separates information in every control pack CONT from thereproduced signal. The video processor 17B feeds the control packinformation to the control unit 23.

Sixth Embodiment

FIG. 40 shows a DVD-Audio player including an audio-signal decodingapparatus according to a sixth embodiment of this invention. The playerin FIG. 40 is designed for a DVD-Audio in FIG. 26.

The player in FIG. 40 operates on a DVD-Audio 1. The player in FIG. 40includes an operation unit 18 and a remote control unit 19. The remotecontrol unit 19 can communicate with the operation unit 18 by wireless.The operation unit 18 is connected to a control unit 23. The controlunit 23 includes a CPU. The control unit 23 is connected to a drive unit2 and a reproduced signal processing unit 17D. The drive unit 2 isconnected to the reproduced signal processing unit 17D.

The CPU 23 operates in accordance with a program stored in an internalROM. When the user actuates the operation unit 18 or the remote controlunit 19 to request tune selection, playback, fast feed, or stop, the CPU23 controls the drive unit 2 and the reproduced signal processing unit17D to implement the requested operation mode.

During playback, the drive unit 2 reads out a signal from the DVD-Audio1. The drive unit 2 includes a demodulator which subjects the readoutsignal to given demodulation (for example, EFM demodulation). The driveunit 2 outputs the demodulation-resultant signal to the reproducedsignal processing unit 17D as a reproduced signal.

The reproduced signal processing circuit 17D includes a video packdetector 3A which receives the reproduced signal from the drive unit 2.The video pack detector 3A detects video packs V (still-picture packsSPCT) in the reproduced signal. The video pack detector 3A generatescontrol parameters in response to the detected video packs V. The videopack detector 3A sets the control parameters in a parameter unit (aparameter memory) 8. The video pack detector 3A sequentially writes thevideo packs V into a video pack buffer 4.

The reproduced signal processing circuit 17D includes a reading unit 5connected to the video pack buffer 4. The reading unit 5 reads out userdata from the video packs V in the video pack buffer 4 in an orderdetermined by SCR information (see FIG. 14) in each of the video packsV. The reading unit 5 outputs a stream of the user data to a pictureconverter 6. The picture converter 6 changes the user data stream into acorresponding digital video signal. The picture converter 6 outputs thedigital video signal to a digital-to-analog (D/A) converter 7. The D/Aconverter 7 changes the digital video signal into a corresponding analogvideo signal. The D/A converter 7 outputs the analog video signal to anexternal device (not shown).

The reproduced signal processing circuit 17D includes an audio packdetector 9A which receives the reproduced signal from the drive unit 2.The audio control pack detector 9A detects audio packs A and real-timeinformation packs RTI in the reproduced signal. The audio pack detector9A generates control parameters in response to the detected audio packsA and the detected real-time information packs RTI. The audio packdetector 9A sets the control parameters in a parameter unit (a parametermemory) 14. The audio pack detector 9A sequentially writes the audiopacks A and the real-time information packs RTI into an audio packbuffer 10.

The reproduced signal processing circuit 17D includes a reading unit 11Aconnected to the audio pack buffer 10. The reading unit 11A reads outuser data (audio data) from the audio packs A in the audio pack buffer10 in an order determined by SCR information (see FIG. 14) in each ofthe audio packs A. The reading unit 11A outputs a stream of the userdata (the audio data) to a PCM converter 12. The PCM converter 12changes the user data stream (the audio data stream) into acorresponding digital audio signal by a PCM decoding process. The PCMconverter 12 outputs the digital audio signal to a digital-to-analog(D/A) converter 13. The D/A converter 13 changes the digital audiosignal into a corresponding analog audio signal. The analog audio signalhas, for example, a left front channel Lf, a right front channel Rf, aleft surround channel Ls, a right surround channel Rs, a center channelC, and a low frequency effect channel LFE. The D/A converter 13 outputsthe analog audio signal to an external device (not shown).

In addition, the reading unit 11A reads out audio character displayinformation (ACD information) from the real-time information packs RTIin the audio pack buffer 10 in an order determined by ISCR informationin each of the real-time information packs RTI. The reading unit 11Aoutputs the audio character display information to a display signalgenerator 20. The display signal generator 20 converts the audiocharacter display information into a corresponding display signal. Thedisplay signal generator 20 outputs the display signal to a displaydevice 21. The display device 21 indicates the display signal. Thedisplay signal generator 20 may output the display signal to an externaldevice (not shown).

The reproduced signal processing unit 17D includes a detector 95 whichreceives the reproduced signal from the drive unit 2. The detector 95extracts information of sampling frequencies “fs” (fs1 and fs2) andinformation of quantization bit numbers Q (Q1 and Q2) from thereproduced signal. The detector 95 feeds the information of the samplingfrequencies “fs” (fs1 and fs2) and the information of the quantizationbit numbers Q (Q1 and Q2) to the CPU 23. The CPU 23 controls the PCMconverter 12 and the D/A converter 13 in response to the information ofthe sampling frequencies “fs” (fs1 and fs2) and the information of thequantization bit numbers Q (Q1 and Q2). Accordingly, conditions of theinverse quantization (the signal decoding) implemented by the PCMconverter 12 and the D/A converter 13 depend on the information of thesampling frequencies “fs” (fs1 and fs2) and the information of thequantization bit numbers Q (Q1 and Q2). Thus, the inverse quantizationcan be on a channel by channel basis or a channel-group by channel-groupbasis.

Seventh Embodiment

FIG. 41 shows a DVD-Audio player including an audio-signal decodingapparatus according to a seventh embodiment of this invention. Theplayer in FIG. 41 is basically similar to the player in FIG. 40.

The player in FIG. 41 operates on a DVD-Audio 1 which has a TOC area 1 aloaded with TOC information. The TOC area 1 a may be included in thelead-in area or in the AST_D. The TOC may be called SAPP (Simple AudioPlay Pointer) for a DVD-Audio disc. The player in FIG. 41 includes acontrol unit 23 connected to an operation unit (not shown). The controlunit 23 includes a CPU. A remote control unit (not shown) cancommunicate with the operation unit by wireless. The control unit 23 isconnected to a reproducing device 2A.

The reproducing device 2A is connected to a TOC detector 2B, an audioprocessor 17A, and a video processor 17B. The TOC detector 2B isconnected to a memory 14A. The memory 14A is connected to the controlunit 23. The audio processor 17A and the video processor 17B areconnected to the control unit 23. The audio processor 17A is connectedto output devices 13A and 13B. The video processor 17B is connected tooutput devices 7A and 7B.

When the DVD-Audio 1 is set in position within the player of FIG. 41,the reproducing device 2A reads out a signal from the TOC area 1 a ofthe DVD-Audio 1. The reproducing device 2A outputs the readout signal tothe TOC detector 2B. The TOC detector 2B detects TOC information in thereadout signal. The TOC detector 2B stores the detected TOC informationinto the memory 14A.

When the user actuates the operation unit or the remote control unit toselect a desired tune, the control unit 23 refers to the TOC informationin the memory 14A and controls the reproducing device 2A in response tothe TOC information to start playback of the desired tune from its head.

During playback, the reproducing device 2A reads out a signal from theDVD-Audio 1. The reproducing device 2A outputs the readout signal to theaudio processor 17A and the video processor 17B as a reproduced signal.The audio processor 17A separates audio data from the reproduced signal.The audio processor 17A feeds the audio data to the output device 13A.The output device 13A converts the audio data into a corresponding audiosignal. The output device 13A feeds the audio signal to an externaldevice (not shown). In addition, the audio processor 17A separatescharacter information (audio character display information) from thereproduced signal. The audio processor 17A feeds the characterinformation to the output device 13B. The output device 13B converts thecharacter information into a corresponding character signal. The outputdevice 13B feeds the character signal to an external device (not shown).Furthermore, the audio processor 17A separates an audio manager AMG andaudio title sets ATS from the reproduced signal. The audio processor 17Afeeds the audio manager AMG and the audio title sets ATS to the controlunit 23.

During playback, the video processor 17B separates video data from thereproduced signal. The video processor 17B feeds the video data to theoutput device 7A. The output device 7A converts the video data into acorresponding video signal. The output device 7A feeds the video signalto an external device (not shown). In addition, the video processor 17Bseparates sub picture information from the reproduced signal. The videoprocessor 17B feeds the sub picture information to the output device 7B.The output device 7B converts the sub picture information into acorresponding sub picture signal. The output device 7B feeds the subpicture signal to an external device (not shown).

Eighth Embodiment

FIG. 42 shows an optical disc player or a DVD-Audio player according toan eighth embodiment of this invention. The DVD-Audio player in FIG. 42includes a demultiplexer 110 which follows a pack reproducing section105. The pack reproducing section 105 reads out a signal from aDVD-Audio, and derives a stream of packs from the readout signal. Thedemultiplexer 110 receives the pack stream from the pack reproducingsection 105.

In the DVD-Audio player in FIG. 42, the demultiplexer 110 is connectedto buffers 131-1, 131-2, 141, and 151. The buffers 131-1 and 131-2 areconnected to a decoder 132. The decoder 132 is connected to a buffer133, and D/A converters 134-1 and 134-2.

The buffer 141 is connected to a decoder 142. The decoder 142 isconnected to buffers 143 and 144. The buffer 144 is connected to adecoder 145. The decoder 145 is connected to a buffer 146.

The buffer 151 is connected to a decoder 152. The decoder 152 isconnected to buffers 153 and 154. The buffer 154 is connected to adecoder 155. The decoder 155 is connected to a buffer 156.

The demultiplexer 110 separates audio packs A from the pack stream. Thedemultiplexer 110 sequentially and alternately writes the separatedaudio packs A into the buffers 131-1 and 131-2. The capacity of each ofthe buffers 131-1 and 131-2 is equal to 4 kilobytes.

In addition, the demultiplexer 110 separates audio control packs A-CONTfrom the pack stream. The demultiplexer 110 sequentially writes theseparated audio control packs A-CONT into the buffer 151.

Furthermore, the demultiplexer 110 separates control packs CONT from thepack stream. The demultiplexer 110 extracts presentation controlinformation PCI from the separated control packs CONT. The demultiplexer110 writes the extracted presentation control information PCI into thebuffer 141.

The decoder 152 reads out information from the audio control packsA-CONT in the buffer 151. The decoder 152 cooperates with the buffer153, thereby decoding the readout information. The decoder 152 informsthe decoder 132 of the decoding-resultant information. The decoder 152separates audio highlight information from the decoding-resultantinformation. The decoder 152 writes the audio highlight information intothe buffer 154. The decoder 155 reads out the audio highlightinformation from the buffer 154. The decoder 155 cooperates with thebuffer 156, thereby decoding the audio highlight information. Thedecoder 155 outputs the decoding-resultant information to an externaldevice (not shown).

The decoder 132 alternately accesses the buffers 131-1 and 131-2 andreads out user data (audio data) from the audio packs A in the buffers131-1 and 131-2. When the buffer 131-1 is accessed by the demultiplexer110, the decoder 132 accesses the buffer 131-2. When the buffer 131-2 isaccessed by the demultiplexer 110, the decoder 132 accesses the buffer131-1. The decoder 132 cooperates with the buffer 133, thereby combiningthe user data into an audio data stream and decoding the audio datastream into a PCM audio signal in response to the information fed fromthe decoder 152. The PCM audio signal has 3 front channels, 2 rearchannels, and one LFE channel. The 3 front channels relate to a samplingfrequency “fs” of 96 kHz. The 2 rear channel and the LFE channel relateto a sampling frequency “fs” of 48 kHz. The decoder 132 outputs the 3front channels of the PCM audio signal to the D/A converter 34-1. Thedecoder 132 outputs the 2 rear channels and the LFE channel of the PCMaudio signal to the D/A converter 34-2. The D/A converter 34-1 changesthe 3 front channels of the PCM audio signal into 3 front channels of acorresponding analog audio signal. The D/A converter 34-1 outputs the 3front channels of the analog audio signal to an external device (notshown). The D/A converter 34-2 changes the 2 rear channels and the LFEchannel of a corresponding analog audio signal. The D/A converter 34-2outputs the 2 rear channels and the LFE channel of the analog audiosignal to an external device (not shown).

The decoder 142 reads out the presentation control information PCI fromthe buffer 141. The decoder 142 cooperates with the buffer 143, therebydecoding the presentation control information PCI into highlightinformation. The decoder 142 writes the highlight information into thebuffer 144. The decoder 145 reads out the highlight information from thebuffer 144. The decoder 145 cooperates with the buffer 146, therebydecoding the highlight information. The decoder 145 outputs thedecoding-resultant information to an external device (not shown).

Ninth Embodiment

FIG. 43 shows an optical disc player or a DVD-Video player according toa ninth embodiment of this invention. The DVD-Video player in FIG. 43includes a demultiplexer 110 which follows a pack reproducing section105. The pack reproducing section 105 reads out a signal from aDVD-Video, and derives a stream of packs from the readout signal. Thedemultiplexer 110 receives the pack stream from the pack reproducingsection 105.

In the DVD-Video player in FIG. 43, the demultiplexer 110 is connectedto buffers 111, 121, 131, and 141. The buffer 111 is connected todecoders 112 and 132. The decoder 112 is connected to a buffer 113, areorder buffer 114, and a switch 115. The reorder buffer 114 isconnected to the switch 115. The switch 115 is connected to a letter boxconverter 116. The letter box converter 116 is connected to an adder117.

The buffer 121 is connected to a decoder 122. The decoder 122 isconnected to the adder 117 and a buffer 123.

The buffer 131 is connected to the decoder 132. The decoder 132 isconnected to a buffer 133.

The buffer 141 is connected to a decoder 142. The decoder 142 isconnected to buffers 143 and 144. The buffer 144 is connected to adecoder 145. The decoder 145 is connected to a buffer 146.

The demultiplexer 110 separates video packs V, audio control packsA-CONT, and control packs CONT from the pack stream. The demultiplexer110 writes the separated video packs V, the separated audio controlpacks A-CONT, and the separated control packs CONT into the buffer 111.

The demultiplexer 110 separates sub picture packs SP from the packstream. The demultiplexer 110 sequentially writes the separated subpicture packs SP into the buffer 121.

The demultiplexer 110 separates audio packs A from the pack stream. Thedemultiplexer 110 sequentially writes the separated audio packs A intothe buffer 131.

In addition, the demultiplexer 110 separates navigation packs from thepack stream. The demultiplexer 110 extracts presentation controlinformation PCI from the separated navigation packs. The demultiplexer110 may extract presentation control information PCI from the separatedcontrol packs CONT. The demultiplexer 110 writes the extractedpresentation control information PCI into the buffer 141.

The decoder 112 reads out user data (video data) from the video packs Vin the buffer 111. The decoder 112 cooperates with the buffer 113,thereby decoding the video data into a corresponding video signal. Thedecoder 112 writes the video signal into the buffer 114. In addition,the decoder 112 outputs the video signal to the switch 115. The switch115 selectively connects the letter box converter 116 to the decoder 112or the reorder buffer 114. When the switch 115 connects the letter boxconverter 116 to the decoder 112, the letter box converter 116 receivesthe video signal from the decoder 112. In this case, the letter boxconverter 116 subjects the received video signal to given conversion.The letter box converter 116 outputs the conversion-resultant signal tothe adder 117. When the switch 115 connects the letter box converter 116to the buffer 114, the letter box converter 116 accesses the videosignal in the buffer 114 and reorders the video signal. In this case,the letter box converter 116 subjects the reordering-resultant videosignal to the given conversion. The letter box converter 116 outputs theconversion-resultant signal to the adder 117.

The decoder 122 reads out video data from the sub picture packs SP inthe buffer 121. The decoder 122 cooperates with the buffer 123, therebydecoding the video data into a sub picture signal. The decoder 122outputs the sub picture signal to the adder 117. The adder 117 combinesthe output signal of the letter box converter 116 and the output signal(the sub picture signal) of the decoder 122 into a sub-picture-addedvideo signal. The adder 117 outputs the sub-picture-added video signalto an external device (not shown).

The decoder 132 reads out information from the audio control packsA-CONT in the buffer 111. In addition, the decoder 132 reads out userdata (audio data) from the audio packs A in the buffer 131 in responseto the A-CONT information. The decoder 132 cooperates with the buffer133, thereby combining the user data into an audio data stream anddecoding the audio data stream into a corresponding audio signal inresponse to the A-CONT information. The decoder 132 outputs the audiosignal to an external device (not shown).

The decoder 142 reads out the presentation control information PCI fromthe buffer 141. The decoder 142 cooperates with the buffer 143, therebydecoding the presentation control information PCI into highlightinformation. The decoder 142 writes the highlight information into thebuffer 144. The decoder 145 reads out the highlight information from thebuffer 144. The decoder 145 cooperates with the buffer 146, therebydecoding the highlight information. The decoder 145 outputs thedecoding-resultant information to an external device (not shown).

1. A digital signal recording disc comprising: a first area (ATS D)storing an audio title set (ATS) which comprises one or more audiopack(s) containing at least first and second channel digital audiosignals of a plurality of channels of audio data, wherein said pluralityof channels are divided into first and second channel groups (Group1,2), and the first channel digital audio signal included in the firstchannel group comprises a front channel digital audio signal (Lf,Rf) andthe second channel digital audio signal(s) included in the secondchannel group comprises a rear channel digital audio signal; the audiotitle set (ATS) including an audio title set information (ATSI)containing information of first and second parameters respectivelyrelating to the first and second channel digital audio signals, thefirst parameter comprising at least one item selected from the groupcomprising; quantization bit numbers (Q1,Q2) of the first and secondgroup channel digital audio signals; sampling frequencies (fs1,fs2) ofthe first and second channel group digital audio signals; the secondparameter (CHANNEL ASSIGNMENT) comprising assignment of the first andsecond channel digital audio signals to said first and second channelgroups; the digital signal recording disc having a second area (VTS D)storing a video title set (VTS); wherein said audio pack having a headerstoring information of first and second parameters respectively relatingto the first and second channel digital audio signals, the firstparameter comprising at least one item selected from the groupcomprising; quantization bit numbers (Q1,Q2) of the first and secondgroup channel digital audio signals; sampling frequencies (fs1,fs2) ofthe first and second channel group digital audio signals; the secondparameter (CHANNEL ASSIGNMENT) comprising assignment of the first andsecond channel digital audio signals to said first and second channelgroups.
 2. A digital signal recording disc as recited in claim 1,wherein the quantization bit numbers of the first and second channeldigital audio signals are different from each other.
 3. A digital signalrecording disc as recited in claim 2, wherein the sampling frequenciesof the first and second channel digital audio signals are different fromeach other.
 4. A method of recording data to or reproducing data fromthe digital signal recording disc of claim
 1. 5. A digital signalrecording disc as recited in claim 1, wherein the audio title set (ATS)comprises an audio-only-title audio-object AOTT-AOB, and the audio titleset information (ATSI) contains an audio-only-title audio-objectattribute AOTT-AOB-ATR for storing the information of first and secondparameters.